An analysis of development and research on spent nuclear fuel reprocessing

Nuclear energy comes back to the discussions on the world stage as an energy source that does not contribute to global warming during production process. It can be chosen as the main source of power generation in some countries or complement the energy matrix in others. In this context, there is the need to develop new technologies for the management of radioactive waste generated by the production process. Final repositories for spent fuel are not yet in commercial operation, and techniques for fuel reprocessing have been developed, because after use, the fuel still has materials that produce energy. Some countries already use reprocessing, and develop research to make it more secure and more competitive, while others prefer to adopt policies to prevent developments in this area due to the problem of nuclear proliferation. In another line of research, new reactors are being developed in order to reduce the amount of waste in energy production and some will be designed to work in closed loop, recycling the materials generated.     

Spent nuclear fuel policies in historical perspective: An international comparison

The purpose of this article is to explain why the world's nuclear power countries differ from each other with respect to their spent nuclear fuel (SNF) policies. The emergence and evolution of three principal SNF approaches are analyzed: direct disposal, reprocessing and SNF export. Five broad explanatory factors are identified and discussed in relation to the observed differences in policy outcomes: military ambitions and non-proliferation, technological culture, political culture and civil society, geological conditions, and energy policy. SNF policy outcomes can generally be seen to result from a complex interaction between these broad factors, but it is also possible to discern a number of important patterns. To the extent that the five factors may undergo far-reaching changes in the future, the historical experience of how they have shaped SNF policies also give a hint of possible future directions in SNF policymaking around the world.     

Implications of the new National Energy Basic Plan for nuclear waste management in Korea

The Korean National Energy Committee has recently adopted a new National Energy Basic Plan according to which the electricity generated by nuclear power plants is to increase from the current 35.5% of total electricity production to 59% by 2030. This large increase in nuclear power will inevitably accelerate the accumulation of spent fuel; if the direct disposal option is pursued, spent fuel arisings in Korea are expected to exceed 100,000 tHM in 2100. It is estimated that the country will require between 10–22 disposal sites, each with an area equal to the Gyeongju low- and intermediate-level radioactive waste (LILW) disposal site, to accommodate this amount of spent fuel. However, considering Korea's geographic profile, securing this number of sites will be almost impossible, and will ultimately create a serious problem for the sustainability of nuclear energy in the country. In view of this dilemma, this paper recommends that the volume of Korean nuclear waste for disposal be significantly reduced, and offers sodium fast reactor (SFR)-based recycling as a potentially viable solution.     

Thermal analysis of a spent fuel cask in different transport conditions

Like all industries, the generation of electricity from Nuclear Power Plant produces wastes to be managed. Spent fuel element casks used for transport of nuclear materials must be designed according to rigorous acceptance criteria and standards requirements, e.g. International Atomic Energy Agency ones, in order to provide protection to people and environment against radiation exposure.The aim of this work was the evaluation of the integrity of spent fuel cask under both normal and accident transport conditions, such as impact (9 m drop impact event onto a flat, essentially unyielding, horizontal surface, in the most damaging orientation) and rigorous fire events (full exposure to an engulfing fire for 30 min (fire test) or to an environment at 800 °C temperature for a numerical simulation or for a furnace test).Using the finite element code ANSYS both steady-state and transient thermal analyses were carried out to determine the maximum fuel temperature and the temperatures behaviour into the cask, considering all the heat transfer modes between the cask and the external environment as well as inside the cask itself. Moreover, both wet and dry fuel storage inside the cavity of the body were analyzed. The obtained results, used for the new licensing approval by the Italian competent Authority of the cask for PWR spent fuel transport, are discussed.     

The struggle for safe nuclear expansion in China

After a temporary halt following the Fukushima nuclear disaster in March 2011, China resumed its fast, yet cautious, expansion of nuclear energy programme. Nuclear energy is considered as part of the general strategy to deal with the challenges of energy security and climate change and to advance with ‘state of the art’ technology in its development. This article briefly discusses recent development in and driving forces behind nuclear industry in China, and several challenges it has been facing: how to adopt, adapt, standardise and indigenise whose technologies, and how to address the shortage of qualified nuclear engineers, scientists, skilled labour force and qualified regulators. More importantly, it argues that safe and secure nuclear development requires consistent policies and effective regulations. Therefore, it is crucial to build policy and regulatory capacities based on coordination, planning and management of government agencies and the industry.     

Choosing a standard reactor: International competition and domestic politics in Chinese nuclear policy

China has ambitious plans to expand its nuclear power capacity. One of the policy goals that high-level policymakers have desired is to base the nuclear program on a standardized reactor design. However, this has not materialized so far. By examining its nuclear reactor choices for individual projects, we argue that China’s policymaking process has been greatly influenced by international competition and domestic politics. Multiple international nuclear vendors are intent upon maintaining their respective niches in the expanding Chinese reactor market, and they have used various forms of economic and political pressure to achieve their objectives. On the other hand, China’s policymaking process is fragmented and the shifting power balances among powerful domestic actors do not allow a fixed path to be followed. Further, because of the high costs and potential profits involved, nuclear reactor choices in China have been driven not just by technical considerations but also by foreign and trade policy objectives. All of these make it unlikely that China will standardize the reactor type it constructs in the near future.     

Comparative study of different nuclear fuel cycle options: Quantitative analysis on material flow

As a nation develops its nuclear strategies, it must consider various aspects of nuclear energy such as sustainability, environmental-friendliness, proliferation-resistance, economics, technologies, and so on. A nuclear fuel cycle study could give convincing answers to many questions in regard to technical aspects. However, one nuclear fuel cycle option cannot be superior in all aspects. Therefore a nation must identify its top priority and accordingly evaluate all the possible nuclear fuel cycle options. For such a purpose, this paper examined four different fuel cycle options that are likely to be plausible under situation of Republic of Korea: once-through cycle, DUPIC recycling, thermal recycling using MOX fuel in PWR (pressurized water reactor), and SFR (sodium cooled fast reactor) employing fuel recycling by a pyroprocess. The options have been quantitatively compared in terms of resource utilization and waste generation based on 1 TWh electricity production at a “steady-state” condition as a basic analysis. This investigation covered from the front-end of the fuel cycles to the final disposal and showed that the Pyro-SFR recycling appears to be the most competitive from these material quantitative aspects due to the reduction of the required uranium resources and the least amount of waste generation.     

A study of the probabilistic risk assessment to the dry storage system of spent nuclear fuel

Due to the large power supply in the energy market since 1960s, the nuclear power planets have been consistently constructed throughout the world in order to maintain and supply sufficient fundamental power generation. Up to now, most of the planets have been operated to a point where the spent fuel pool has reached its design capacity volume. To prevent the plant from shutdown due to the spent fuel pool exceeding the design capacity, the dry cask storage can provides a solution for both the spent fuel pool capacity and the mid-term storage method for the spent fuel bundles at nuclear power planet.     

China's spent nuclear fuel management: Current practices and future strategies

Although China's nuclear power industry is relatively young and the management of its spent nuclear fuel is not yet a concern, China's commitment to nuclear energy and its rapid pace of development require detailed analyses of its future spent fuel management policies. The purpose of this study is to provide an overview of China's fuel cycle program and its reprocessing policy, and to suggest strategies for managing its future fuel cycle program. The study is broken into four sections. The first reviews China's current nuclear fuel cycle program and facilities. The second discusses China's current spent fuel management methods and the storage capability of China's 13 operational nuclear power plants. The third estimates China's total accumulated spent fuel, its required spent fuel storage from present day until 2035, when China expects its first commercialized fast neutron reactors to be operational, and its likely demand for uranium resources. The fourth examines several spent fuel management scenarios for the present period up until 2035; the financial cost and proliferation risk of each scenario is evaluated. The study concludes that China can and should maintain a reprocessing operation to meet its R&D activities before its fast reactor program is further developed.     

The world nuclear power scene and UK energy policy in 1984

The world nuclear scene is a patchwork, with a crisis of confidence in most Western countries (with France as the outstanding exception), steady progress in the Eastern bloc, and mixed experience in the LDCs — partly because of lack of interest by developed countries in the production and marketing of small robust nuclear plants with suitable back-up services. The situation in the UK is a microcosm of that in the Western world as a whole. It is compounded by the absence of any coherent energy policy other than an unspoken one of reliance on market forces, combined with short-term expediency, as the dominating element in decisions needing to be taken on individual energy industries.     

An international comparative analysis of public acceptance of nuclear energy

Across the globe, public acceptance of nuclear power is a crucial factor for governmental establishment of a nuclear energy program. Therefore, it is important to understand the determinants of public acceptance of nuclear power. This study examines the effects of knowledge, trust, risk, and benefit related factors on public acceptance of nuclear power across 19 countries. We consider three levels of public acceptance – strongly accept, reluctantly accept, and oppose – and classify countries into four groups according to the ratio of those three levels of public acceptance. Our results indicate that knowledge of nuclear inspection is more effective than trust in inspection authorities in creating stronger public acceptance among people in the countries with a high level of reluctant acceptance and a low level of strong acceptance, while trust in inspection authorities is more important than knowledge of nuclear inspection for the selection between opposition and reluctant acceptance in countries with a low level of reluctant acceptance and a high level of strong acceptance. Without grouping the countries, we found that trust in inspection authorities is crucial for the decision between opposition and reluctant acceptance. Additionally, the generation of electricity has the most positive effect on public acceptance of nuclear power.     

The analysis of some nuclear power integrated systems

This paper define the concept of the nuclear power integrated system as a fast-thermal one. the integration with three successive fast reactor generations is considered: first reactor genertion—LMFBR(PuO₂); second reactor generation-LMFBR(CPu); and third reacator generation—GCFBR(PuO₂). A time interval of [0, 40] years is considered and the time evolution of the integrated system is followed under the following circumstances: a time delay of 15 years in the case of the first reactor generation, 20 years in the case of the second reactor generation and 25 years in the case of the third reactor generation. By applying the mathematical model of integrated systems an analysis of the three nuclear power integrated systems is made and many important conclusions of interest to decision makers are also drawn.     

A feasibility study on direct methanol fuel cells for laptop computers based on a cost comparison with lithium-ion batteries

This paper compares the total cost of direct methanol fuel cell (DMFC) and lithium (Li)-ion battery systems when applied as the power supply for laptop computers in the Korean environment. The average power output and operational time of the laptop computers were assumed to be 20 W and 3000 h, respectively.     

Development of a mesoscopic particle model for synthesis of uranium-ceramic nuclear fuel

A novel technique has been developed to fabricate uranium-ceramic nuclear fuel using the depleted uranium (DU), U₃O₈ powder, and allylhydridopolycarbosilane (AHPCS) polymer precursor. This process involves a continuous change of the composition, porosity, and material properties. To fabricate nuclear fuel with a uniform structure/volume ratio, it is important to understand the transport phenomena during high temperature processing and at different length scales. In our prior work, a system-level model based on the reactive porous medium theory was developed to account for pyrolysis process during the uranium-ceramic fuel fabrication. In this paper, a mesoscopic model based on the smoothed particle hydrodynamics (SPH) is developed to simulate the synthesis of filler U₃O₈ particles and SiC matrix. The system-level model provides the necessary thermal boundary conditions for the mesoscopic simulation. The evolution of the particle concentration and the structure as well as the composition of the composite produced is investigated. Since the process heat flux plays an important role in the material quality and uniformity, the effect of the heating rate, filler particle size and distribution on the uniformity and the structure of the final product are investigated. The uncertainty issue is also discussed.     

Future regional nuclear fuel cycle cooperation in East Asia: Energy security costs and benefits

Economic growth in East Asia has rapidly increased regional energy, and especially, electricity needs. Many of the countries of East Asia have sought or are seeking to diversify their energy sources and bolster their energy supply and/or environmental security by developing nuclear power. Rapid development of nuclear power in East Asia brings with it concerns regarding nuclear weapons proliferation associated with uranium enrichment and spent nuclear fuel management. This article summarizes the development and analysis of four different scenarios of nuclear fuel cycle management in East Asia, including a scenario where each major nuclear power user develops uranium enrichment and reprocessing of spent fuel individually, scenarios featuring cooperation in the full fuel cycle, and a scenario where reprocessing is avoided in favor of dry cask storage of spent fuel. The material inputs and outputs and costs of key fuel cycle elements under each scenario are summarized.     

A comparison of the nuclear options for greenhouse gas mitigation in China and in the United States

China is quickly building up its nuclear power capacity while the hailed nuclear renaissance in the United States has been largely stagnant. The political and industrial structures explain the divergent paths. This paper draws lessons from the French experiences in deploying nuclear power and uses the lessons in comparing Chinese and U.S. policies. An authoritative political system and state-owned utility industry allow China to emulate the French approaches such as government-backed financing and broad-scale deployment with standardized design. The democratic political system and fragmented utility industry, and the laissez-faire ideology in the United States, on the other hand, are unfavorable to a nuclear renaissance. The prospect of a nuclear revival in the United States remains highly uncertain.     

Conditioned minimization of fuel feed rate for a CANDU-600 MWe reactor

A nonlinear programming optimization problem is considered for the case in which the decision vector is the vector of zonal irradiation while the objective function is the equilibrium fuel feed rate with a CANDU-600 reactor subject to certain restrictions regarding the reactivity excess and the maximum powers per channel and bundle. The objective and restriction functions of the system are estimated within a time average approximation of a three-dimensional two-group diffusion type, with the control systems uniformly immersed within the reactor, and also considering the newest increments of the parasitic absorbents using FMDP program. The optimization problem is solved by means of the SUMT method, modified so as to become a technique of sequential solving for certain subproblems of linear optimization through the application of LPROG program. The results are presented as optimal vectors of zonal irradiation and as optimal values of fuel feed rate, with some two-zone cases, which establish the best zonal configuration. This configuration is then extended to a four-zone case which is analysed in a similar manner, evidencing a saving potential which gives the possibiliy of increasing the reactor performance.     

Communication on energy An alternative projection model of future nuclear capacity

There is generally a high degree of uncertainty involved in the projection of growth of any energy source, especially when the projection extends 50 years ahead. The 1982 OECD/NEA Report, ‘Nuclear Energy and its Fuel Cycle Prospect to 2025’ notes the downturn in past projections of nuclear capacity over the past decade. It is obvious that rapidly changing conditions have affected overall worldwide energy and economic growth and the field of nuclear power has been subject to changes specific to itself. These have caused past projections to become obsolete and therefore it would seem necessary to implement a new projection method to improve the accuracy of present forecasting.     

Prospects for introducing hydrogen fuel cell vehicles in Malaysia

Sustainable economic development through adoption of hydrogen pathway is expected to simultaneously solve the double challenge of environment and energy security. The momentum of current research in this area is focused on optimizing the potential benefits in transportation sector through introduction of hydrogen fuel cell vehicles (FCVs). However the rapid adoption of critical cleaner energy system is still problematic in developing countries especially in transportation. This article sheds light on the Malaysian case by highlighting related issues and obstacles, and discusses the future prospects of hydrogen FCV. We argue that innovation and technological advancement of hydrogen FCV is important and ready for introduction in Malaysia; however it is not sufficient in explaining the conditions that will allow for rapid transition in Malaysia. The main message of this article is that hydrogen FCV in Malaysia can be expected and is possible when there is a thorough understanding of energy security issues, where energy policy integration for economic development and environmental objectives are achieved at the same time. The understanding of specific problems from the standpoint of developing country is crucial in encouraging government policies to induce development of hydrogen FCV.     

Thermodynamic analysis of a Proton Exchange Membrane fuel cell

In this study, energy and exergy analyses of a 1 kW Horizon H-1000 XP Proton Exchange Membrane (PEM) Fuel Cell has been investigated. A testing apparatus has been established to analyze the system efficiencies based on the first and second laws of thermodynamics. In this mechanism pure hydrogen has been directly used as a fuel in compressed gas formation. Purity of hydrogen was above 99.99%. The system performance was investigated through experimental studies on energy and parametric studies on exergy by changing the operating pressure and operation temperature. The results showed that the energy efficiency of PEM fuel cell is 45.58% for experimental study and 41.27% for parametric study at full load. Also, 2.25% and 4.2% performance improvements were obtained by changing the operating temperature ratio (T/T₀) from 1 to 1.2 and operating pressure ratio (P/P₀) from 1 to 2, respectively.