Nuclear proliferation-resistance and safeguards for future nuclear fuel cycle

Corresponding to the world nuclear security concerns, future nuclear fuel cycle (NFC) should have high proliferation-resistance (PR) and physical protection (PP), while promotion of the peaceful use of the nuclear energy must not be inhibited. In order to accomplish nuclear non-proliferation from NFC, a few models of the well-PR systems should be developed so that international community can recognize them as worldwide norms. To find a good balance of ‘safeguard-ability (so-called extrinsic measure or institutional barrier)’ and ‘impede-ability (intrinsic feature or technical barrier)’ will come to be essential for NFC designers to optimize civilian nuclear technology with nuclear non-proliferation, although the advanced safeguards with high detectability can still play a dominant role for PR in the states complying with full institutional controls. Accomplishment of such goal in a good economic efficiency is a future key challenge.     

Innovative Nuclear Energy Systems and the Future of Nuclear Power

There is a renewed interest in nuclear power worldwide. The interest is sparked by concerns about global warming and security of energy supplies. In addition to the growing interest in building more reactors in countries that already have nuclear power, future demands for nuclear power are likely to include applications in countries that do not presently use nuclear power and applications beyond large-scale electricity generation. This paper will discuss some of the characteristics that future reactors will need to have to meet such demands, as well as other measures required to facilitate a nuclear renaissance. In addition, the emergence of new international nuclear initiatives and their potential roles will be described.     

Examining relationship between nuclear proliferation and civilian nuclear power development

This paper attempts to examine the relationship between nuclear weapons proliferation and civilian nuclear power development based on the history of Atoms for Peace Initiative. To investigate the relationship, a database was established by compiling information on a country's civilian nuclear power development and various national capabilities and situational factors. The results of correlation analysis indicated that the initial motivation to develop civilian nuclear power could be mostly dual purpose. However, for a civilian nuclear power program to be ultimately successful, the study finds the role of nuclear nonproliferation very important. The analysis indicated that the presence of nuclear weapons in a country and serious interest in nuclear weapons have a negative effect on the civilian nuclear power program. The study showed the importance of state level commitment to nuclear nonproliferation for the success of civilian nuclear power development. NPT ratification and IAEA safeguards were very important factors in the success of civilian nuclear power development. In addition, for a country's civilian nuclear power development to be successful, the country needs to possess strong economic capability and be well connected to the world economic market through international trade. Mature level of democracy and presence of nuclear technological capabilities were also found to be important for the success of civilian nuclear power program.     

Safety aspects of the combined HTTR/steam reforming complex for nuclear hyrogen production

The High-Temperature Engineering Test Reactor (HTTR) in Oarai, Japan, has the potential to demonstrate the production of hydrogen by steam reforming and using nuclear process heat as primary energy input. Particular safety aspects for such a combined nuclear/chemical complex have been investigated such as fire and explosion hazard at presence of flammable gases (LNG, H₂, CO) near the reactor building. A methane vapor cloud in the open atmosphere or partially obstructed areas is highly unlikely to detonate and damage the reactor building. Theoretical assessments and experimental studies significant to the HTTR-steam reforming system, include the spreading and combustion behavior of cryogens and flammable gases providing the basis for a comprehensive safety analysis of the nuclear/chemical facility.     

Disposal of high level nuclear wastes： Thermodynamic equilibrium and environment ethics

Contamination of soil, water or air, due to a failure of containment or disposal of high level nuclear wastes, can potentially cause serious hazards to the environment or human health. Essential elements of the environment and radioactivity dangers to it are illustrated. Issues of high level nuclear waste disposal are discussed with a focus on thermodynamic equilibrium and environment ethics. Major aspects of the issues are analyzed and described briefly to build a perception of risks involved and ethical implications. Nuclear waste containment repository should be as close as possible to thermodynamic equilibrium. A clear demonstration about safety aspects of nuclear waste management is required in gaining public and political confidence in any possible scheme of permanent disposal. Disposal of high level nuclear waste offers a spectrum of environment connected challenges and a long term future of nuclear power depends on the environment friendly solution of the problem of nuclear wastes.     

CO2 and the world energy system: the role of nuclear power

The greenhouse effect, and other transnational and global environment, health and safety issues, require energy system planning on an international scale. Consideration of equity between nations and regions, particularly between the industrialized and developing countries, is an essential ingredient. For the immediate future, the next several decades at least, fossil fuels will remain the predominant energy sources. More efficient use of energy seems to be the only feasible strategy for the near to mid-term to provide growing energy services for the world economy while moderating the increasing demand for fossil fuels. In the longer term, nonfossil sources are essential for a sustainable world energy system, and nuclear power can play an important, if not dominant, role. The challenge is to design and implement a safe and economic nuclear power world enterprise which is socially acceptable and is complimentary to other nonfossil sources. The elements of such an enterprise seem clear and include: much safer reactors, preferably passively safe, which can be deployed at various scales; development of economic resource extension technologies; effective and permanent waste management strategies; and strengthened safeguards against diversion of nuclear materials to weapons. All of these elements can best be developed as cooperative international efforts. In the process, institutional improvements are equally as important as technological improvements; the two must proceed hand-in-hand.     

Nuclear power technologies at the stage of sustainable nuclear power development

It is not simple to solve the problem of competitiveness of nuclear power technologies in evolutionary upgrading the conventional nuclear power plants (NPP) such as light water reactors (LWR), which requires high expenditure for safety. Moreover, the existing LWRs cannot provide nuclear power (NP) for a long time (hundreds of years) because the efficiency of use of natural uranium is low and closing the nuclear fuel cycle (NFC) for those reactors is not expedient.The highlighted problem can be solved in the way of use of innovative nuclear power technology in which natural uranium power potential is used effectively and the intrinsic conflict between economic and safety requirements has been essentially mitigated.The technology that is most available and practically demonstrated is the use of reactors SVBR-100 — small power multi-purpose modular fast reactors (100 MWe) cooled by lead-bismuth coolant (LBC). This technology has been mastered for nuclear submarines’ reactors in Russia.High technical and economical parameters of the NPP based on RF SVBR-100 are determined from the fact that the potential energy stored in LBC per a volume unit is the lowest.The compactness of the reactor facility SVBR-100 that results from integral arrangement of the primary circuit equipment allows realizing renovation of power-units LWRs, the vessels’ lifetime of which has been expired. So due to this fact, high economical efficiency can be obtained.The paper also validates the economical advantage of launching the uranium-fueled fast reactors with further changeover to the closed NFC with use of plutonium extracted from the own spent nuclear fuel in comparison with launching fast reactors directly with on uranium-plutonium fuel on the basis of plutonium extraction from spent nuclear fuel of LWRs.     

Securing the radiological safety of people and the environment at all stages of the life cycle of floating nuclear heat-and-power plants

A floating nuclear heat-and-power plant utilizes atomic energy to supply heat and electricity in remote coastal territories. The danger for people and the environment together with cost-effectiveness will be the decisive factors in choosing such a plant as a source of energy. Validation is given for the need to develop the concept of human and environmental safety security for future, serially produced, floating nuclear heatand-power plants.     

浮动核电站跨界转运的安全和法律问题初步研究

浮动核电站具有模块化、多用途、可移动、运行灵活、适应性强等优势,受到了国际社会的广泛关注,具有广阔的应用前景和发展空间。然而,浮动核电站由于特殊的海外部署场景和可移动特性,不可避免地面临着跨越主权边界转运的安全和法律问题。结合浮动核电站不同的海外部署场景,重点对浮动核电站在不同部署场景下跨界转运可能面临的安全和法律问题进行梳理总结和讨论分析,并从法律、安保和应急层面提出可能的解决方案建议,对浮动核电站跨界转运相关的国际公约和规则制定具有一定参考意义。     

核安全文化与核安保文化的共生性研究

在核能利用领域,核安全和核安保一直是国际社会积极推进的两大安全议题。积极推进核安全与核安保文化的建设是当前我国国家核安全治理的必然要求。核安全文化与核安保文化在最终目的、运行基础和实施载体上存在着一致性;在政策支持、监管设计、组织责任、管理活动和员工行为等层面存在着不可分割性,从而为两个文化体系的互利共生和协同运行提供了可行性。     

Expected role of nuclear science and technology to support the sustainable supply of energy in Indonesia

Energy resources are available in Indonesia but small per capita. The increase of oil price and its reserve depletion rate dictates to decrease the oil consumption. Therefore, it is imperative to increase the shares of other fossils as well as the new and renewable sources of energy in various energy sectors substituting the oil. The introduction of nuclear power plant becomes more indispensable, although the share is to be small but significantly important for electric generation in Java–Madura–Bali grid. Nuclear technology can have also important role enabling the increase of the shares of renewable, e.g. geothermal, hydro and bio-fuels as well as fossil energies to meet more sustainable energy mix sufficing the energy demand to attain intended economic and population growths while maintaining the environment. The first introduced nuclear power plant is to be the proven ones, but the innovative nuclear energy systems being developed by various countries will eventually also be partially employed to further improve the sustainability. The nuclear science and technology are to be symbiotic and synergistic to other sources of energy to enhance the sustainable supply of energy.     

Hydrogen and its relationship with nuclear energy

In broad terms it is estimated that the world will need 17 TW of additional primary energy to meet its needs by 2050. Much of this growth in energy demand will take place in developing countries. Wind, biomass, solar, nuclear and coal will all compete to fill this gap as oil market share declines. Economics, environmental issues, and public acceptance elements of sustainable development goals will be as important as the engineering issues of efficiency and reliability in this competition.

Nuclear power is increasingly recognized as a principal contender to provide economic, “carbon free” electricity for the grid, but it does not directly provide a transportation fuel as flexible as is gasoline. Nuclear-produced hydrogen might help to fill this transportation fuel gap. This presentation will discuss the processes for manufacture of hydrogen from nuclear heat, and the integration of nuclear-produced hydrogen into the transportation fuel system – in part via synergies with traditional oil, natural gas and coal, and/or synergies with nontraditional shale and tar sands. We will discuss the nuclear hydrogen system as we expect it to appear in 2050 and will discuss some of processes that will provide a pathway to creating that system.     

Safety challenges in Spain's nuclear industry according to sector experts

Safety is a key aspect for the continuity of nuclear energy as one of the most widely used energy options worldwide for producing electricity. However, previous studies have shown that the nuclear industry needs to meet social, technological, normative, environmental, economic, and organizational challenges. Due to this need, this study attempts to understand the challenges that Spain's nuclear industry faces with regard to safety. The study was conducted with 122 experts who responded to the question: “What is the main challenge that Spain's nuclear industry faces in the field of safety?” A discourse analysis was performed to identify the most important challenges and how they are characterized by experts.Findings have shown that Spain's nuclear industry must face multiple and very diverse challenges. The main social challenge is the high concern for the continuity of Spain's nuclear industry, generated in large part by the socio-political context of uncertainty and the lack of social acceptance. Technologically, lifetime extension of the nuclear facilities in operation is the main challenge. The experts do not note other challenges present within the industry, such as ensuring new technological developments or building new nuclear plants. Regarding normative challenges, integrating new requirements within the current regulatory framework and coordinating the extensive and diverse existing regulation are noteworthy. The main economic challenge lies in achieving an efficient economic management system that ensures the nuclear plants' operation and makes them profitable. Organizationally, the main challenges are the generational shift and organizational learning. It is noted that the experts do not indicate other organizational issues that have been involved in important events within Spain's nuclear industry. Finally, the experts do not indicate any environmental challenges related to safety.     

Transportable nuclear power facilities in the INPRO International Project

Questions concerning safety, nonproliferation, monitoring of nuclear materials, civilian responsibility for nuclear risks, physical protection, transport operations, and others are analyzed within the framework of the INPRO project in application to transportable nuclear energy facilities. Essentially, the operative nuclear law and the experience of world nuclear power make it possible to solve the problems of the legal basis for the life cycle of transportable nuclear power facilities. To attain a system with the optimal accessibility, effectiveness, and safety, the nuclear power facilities will have to be adapted to the new specific requirements and conditions, and the international legal basis will have to be made more precise.     

Recommendations on legislative and regulatory framework and regulatory body of nuclear security in China

This paper describes the definition of nuclear security that has been changing from the cold war age to the post-911 period, and clarifies the close relationship and yet a clear distinction between nuclear security, nuclear safety and nuclear safeguard. Based on analyses of the current state of nuclear security activities in China as well as the requirements and the law infrastructure, a legislative and regulatory framework of nuclear security and the mandate of a regulatory body in China are recommended.     

Secure Software Configuration Management Processes for nuclear safety software development environment

The main difference between nuclear and generic software is that the risk factor is infinitely greater in nuclear software – if there is a malfunction in the safety system, it can result in significant economic loss, physical damage or threat to human life. However, secure software development environment have often been ignored in the nuclear industry. In response to the terrorist attacks on September 11, 2001, the US Nuclear Regulatory Commission (USNRC) revised the Regulatory Guide (RG 1.152-2006) “Criteria for use of computers in safety systems of nuclear power plants” to provide specific security guidance throughout the software development life cycle. Software Configuration Management (SCM) is an essential discipline in the software development environment. SCM involves identifying configuration items, controlling changes to those items, and maintaining integrity and traceability of them. For securing the nuclear safety software, this paper proposes a Secure SCM Processes (S²CMP) which infuses regulatory security requirements into proposed SCM processes. Furthermore, a Process Flow Diagram (PFD) is adopted to describe S²CMP, which is intended to enhance the communication between regulators and developers.     

Quality assurance for a nuclear power plant simulator by applying standards for safety-critical software

Nuclear power plant simulators are playing a more important role in nuclear power plant lifecycle analysis, and the quality of the simulators should be verified to ensure the safety of nuclear power plants. Currently, there is no systematic quality assurance method for nuclear power plant simulators. In this paper, a systematic quality assurance method for nuclear power plant simulators is proposed basing on experiences with safety-critical software. Key aspects of the method are discussed. In addition, application of this method to a real project is also described as a practical reference.     

Are shocks to nuclear energy consumption per capita permanent or temporary? A global perspective

This paper aims to examine the integration properties of nuclear energy consumption per capita by applying the panel unit root test with structural breaks in 27 countries over the period 1993–2013. To obtain comprehensive and exhaustive information, we utilize the longitudinal clustering approach to segment the overall sample into four sub-samples. We find that for the overall sample, nuclear energy consumption is stationary, while two sub-samples contain unit roots. These results imply that shocks to global nuclear energy consumption will only result in temporary deviations from the long-run growth path; however, shocks have a permanent effect on nuclear energy consumption in two sub-samples. Several implications are provided: if shocks have a lasting effect on nuclear energy consumption, policy makers should design energy conservation and stabilization policies in these countries; otherwise, we do not intervene in the process of nuclear energy consumption.     

Use of the MCNP-polimi code for time-correlation safeguards measurements

Active nuclear safeguards measurements that rely on the time correlation between fast neutrons and gamma rays from the same fission are becoming a useful technique. In previous works we have shown the feasibility of this method, in conjunction with the use of the well-known MCNP simulation code and the use of artificial neural networks, to estimate the mass and enrichment of fissile samples enclosed in special, sealed containers.

In a more recent works, we pointed out some features of MCNP that represent a drawback in the simulation of correlation measurements. In fact, MCNP is not intended for obtaining second order moments. Therefore, to achieve an agreement between the simulations and the experiment, we resorted to the use of effective physical parameters (for example detection threshold and light output). Recently, by suitably modifying MCNP, we developed the MCNP-PoliMi code, which attempts to simulate the physics of each interacton more realistically.

In this paper, we present the results of the calibration of a plastic scintillator using a Cf-252 source, traditionally used in the above-mentioned nuclear safeguards experiments. We show that the physical parameters found by calibration and used in the MCNP-PoliMi simulations are reasonable for this type of detector, and that the correlation functions thereby obtained are in good agreement with the experiment.