LUCIANO ONDIR FREIRE
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Artigo IPEN-doc 28252 On the commercial feasibility of decommissioning a nuclear power plant ship2021 - S. JUNIOR, ADALBERTO; FREIRE, LUCIANO O.; ANDRADE, DELVONEI A. deArtigo IPEN-doc 27928 Potential advantages of molten salt reactor for merchant ship propulsion2021 - FREITAS NETO, LUIZ G. de; FREIRE, LUCIANO O.; SANTOS, ADIMIR dos; ANDRADE, DELVONEI A. deOperating costs of merchant ships, related to fuel costs, has led the naval industry to search alternatives to the current technologies of propulsion power. A possibility is to employ nuclear reactors like the Russian KLT-40S, which is a pressurized water reactor (PWR) and has experience on civilian surface vessels. However, space and weight are critical factors in a nuclear propulsion project, in addition to operational safety and costs. This work aims at comparing molten salt reactors (MSR) with PWR for merchant ship propulsion. The present study develops a qualitative analysis on weight, volume, overnight costs, fuel costs and nuclear safety. This work compares the architecture and operational conditions of these two types of reactors. The result is that MSR may produce lower amounts of high-activity nuclear tailings and, if it adopts the U233-thorium cycle, it may have lower risks of proliferating nuclear weapons. Besides proliferation issues, this 4th generation reactor may have lower weight, occupy less space, and achieve the same levels of safety with less investment. Thus, molten salt regenerative reactors using the U233-thorium cycle are potential candidates for use in ship propulsion.Artigo IPEN-doc 26386 Proposal for a nuclear power-plant ship decomissioning2019 - SOBREIRO JUNIOR, ADALBERTO R.; FREIRE, LUCIANO O.; ANDRADE, DELVONEI A. deThe goal of this work is to review decommissioning methods for nuclear propulsion ships throughout of survey on decommissioning experience. Governmental regulation typically dictates cleanup of a decommission site. It is satisfying the stringent regulations that prove to be a primary cost driver for decommissioning and waste disposal. Reactor types and sizes, the number of reactors on an individual plant site, and labor costs are among the main factors affecting costs. Thus, it is so important to develop a good recycling policy after nuclear-power plant ship inactivation. This work found that adequate requirements identification must keep economics always in the center of design. Experience shows, except after major catastrophic accidents, nuclear industry may earn public trust by open dialogue with the population and sound engineering practices, searching for right technical solution and great planning for long time. To achieve this goal, this work proposed the following method: firstly, it presents the characteristics of nuclear-powered submarines. Secondly, an approach concerning the decommissioning process of nuclear-powered submarines adopted by the US Navy, Russian Navy, Royal Navy, French Navy and others which brings the past experience on this field, providing some information on history, architectures and hints of reasons for the success or failures of each project. Finally, this works compared the decommissioning processes of these navies under the perspective of the nuclear regulatory process.Artigo IPEN-doc 26334 Potential advantages of molten salt reactor for merchant ship propulsion2019 - FREITAS NETO, LUIZ G.; FREIRE, LUCIANO O.; SANTOS, ADIMIR dos; ANDRADE, DELVONEI A. deOperating costs of merchant ships, related to fuel costs, has led the naval industry to search alternatives to the current technologies of propulsion power. A possibility is to employ nuclear reactors like the Russian KLT-40S, which is a pressurized water reactor (PWR) and has experience on civilian surface vessels. However, space and weight are critical factors in a nuclear propulsion project, in addition to operational safety and costs. This work aims at comparing molten salt reactors (MSR) with PWR for merchant ship propulsion. The present study develops a qualitative analysis on weight, volume, overnight costs, fuel costs and nuclear safety. This work compares the architecture and operational conditions of these two types of reactors. The result is that MSR may produce lower amounts of high-activity nuclear tailings and, if it adopts the 233U-thorium cycle, it may have lower risks of proliferating nuclear weapons. Besides proliferation issues, this 4th generation reactor may have lower weight, occupy less space, and achieve the same levels of safety with less investment. Thus, molten salt regenerative reactors using the 233U-thorium cycle are potential candidates for use in ship propulsion.Tese IPEN-doc 25448 Metodologia de especificação e projeto aplicado a usinas nucleares móveis2018 - FREIRE, LUCIANO O.A importância de métodos de projeto vem crescendo nos últimos anos à medida que sistemas sócio-técnicos complexos se tornam mais numerosos. Além da complexidade, o tamanho e o investimento financeiro destes sistemas amplificam a gravidade dos erros de projeto. O objetivo geral deste trabalho foi desenvolver uma metodologia de especificação e projeto que reduza o tempo e energia para desenvolver um sistema complexo cujas funções sejam conhecidas a priori, gerenciando em paralelo os riscos. O objetivo específico foi verificar a viabilidade econômica de usinas nucleares móveis de pequeno porte. Este trabalho adotou como princípio a lei construtal que prevê o sucesso de sistemas que facilitem os fluxos necessários à sua existência. Após a identificação dos fatores chave para facilitar o fluxo de informações, esta tese desenvolveu um conjunto de conceitos para facilitar o trabalho de engenharia. Aplicando tais conceitos, este trabalho desenvolveu sequências de atividades que descrevem o método proposto, sendo cada atividade detalhada por uma lista de requisitos. A demonstração das vantagens do método proposto foi feita por meio de análise de árvore de eventos e árvore de falhas. Usando o método, esta tese desenvolveu especificações e projetos em vários níveis (empresarial, usina, caldeira nuclear, circuito primário e gerador de vapor). Baseando-se em dados da marinha americana, esta tese desenvolveu um modelo de custo para reatores de pequeno porte. Concluiu que a energia nuclear pode ser competitiva se a potência elétrica média efetiva ao longo da vida útil ficar acima de 30MWe e se o tempo de vida útil for igual ou maior do que 60 anos. Tal fato decorre dos altos custos de aquisição que requerem uma vida longa para compensar o investimento e dos efeitos de economia de escala especialmente pronunciados para reatores a água pressurizada.