PAULO ERNESTO DE OLIVEIRA LAINETTI
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Artigo IPEN-doc 23509 Decommissioning of uranium pilot plants at IPEN-CNEN/SP: facilities dismantling, decontamination and reuse as new laboratories for strategic programs2016 - LAINETTI, PAULO E. de O.; FREITAS, ANTONIO A. de; VASQUES, FRANCISCO M.F.; FERREIRA, ROBSON de J.; COTRIM, MARYCEL E.B.; PIRES, MARIA A.F.From beginning of 90’s, the Brazilian nuclear policy has been changed radically. This determined the interruption of most R&D fuel cycle activities and the facilities shutdown at Nuclear and Energetic Research Institute (IPEN). The existence of those facilities also implicated in the need of constant surveillance, representing additional obligations, costs and problems. The reasons to promote the dismantling of the IPEN’s Nuclear Fuel Cycle Pilot Plants elapsed mainly from the need of physical space for new activities, since the R&D in the nuclear fuel cycle area were interrupted. In the last decade, IPEN has changed its “nuclear profile” to a “comprehensive and multidisciplinary profile”. With the end of most nuclear fuel cycle activities, the former facilities were distributed in four different centers. Each center has adopted a different strategy and priority to face the D&D problem. The available resources depend on the specific program in each area’s development (resources available from other sources, not only from Brazilian National Nuclear Energy Commission (CNEN). One of those new activities is the IPEN’s Environmental Program. This paper describes the procedures, problems faced and results related to the reintegration of the former pilot plant areas as new laboratories of the Chemical and Environmental Technology CenterCQMA of the IPEN.Artigo IPEN-doc 23511 Use of dopants for thoria sintering temperature reduction-characterization of THO22016 - TAKIISHI, HIDETOSHI; GENOVA, LUIS A.; CAVALHEIRA, ELTON D.; COTRIM, MARYCEL B.; SANTOS, WILSON; LAINETTI, PAULO E.O.Thorium is nearly three times more abundant than uranium in the Earth’s crust. Some papers evaluate the thorium resources in Brazil over 1,200,000 metric t. These figures mean that the country is probably the biggest thorium resource in the world, with only part of the territory prospected. Nevertheless, Brazil has not a research program for use of thorium in nuclear reactors, even having dedicated special attention to the subject in the beginning of its nuclear activities, in the fifties and sixties. From 1985 until 2003 IPEN operated a pilot plant for thorium nitrate production and purification, used by Brazilian industry for production of gas mantles. This facility produced over 170 metric t of thorium nitrate. Despite the non-nuclear application, the pilot plant was unique in the southern hemisphere. On the other hand, Brazil has the biggest world niobium resources. The Brazilian thorium and niobium resources added to the predictable future importance of alternative fissile materials have motivated this research, since uranium is a finite resource if used in the present thermal nuclear reactors. Besides this, thorium oxide is an important nuclear reactor material. It is a refractory oxide and its ceramic fabrication process involves a very high temperature sintering treatment considering that thoria melting point is very high (3,650 K). Cations of elements of the group VB (V, Nb and Ta) have a known effect in the reduction of thoria sintering temperature. IPEN has initiated an investigation about the use of niobium as a dopant for thoria sintering temperature reduction. The thoria used in the research was produced in the IPEN’s pilot plant and different amounts of niobium oxide (Nb2O5) will be added to thoria by different routes. The powders will be compressed and the compacted pellets will be sintered at different temperatures. The influence of the different parameters in the density of sintered pellets is being investigated. This paper presents the chemical and physical characterization for the thoria used in the investigation.Artigo IPEN-doc 23505 Cutting techniques for facilities dismantling in decommissioning projects2016 - LAINETTI, PAULO E.O.Fuel cycle related activities were accomplished in IPEN-CNEN/SP in laboratory and pilot plant scale and most facilities were built in the 70-80 years. Nevertheless, radical changes of the Brazilian nuclear policy in the beginning of 90’s determined the interruption of several fuel cycle activities and facilities shutdown. Some laboratory and pilot plant decommissioning activities have been performed in IPEN in the last years. During the operational activities in the decommissioning of old nuclear fuel cycle facilities, the personnel involved in the task had to face several problems. In old facilities, the need of large components dismantling and material removal use to present some difficulties, such as lack of available and near electricity supply. Besides this, the spread out of the superficial contamination in the form of dust or aerosols and the exposure of workers should be as much as possible avoided. Then, the selection and availability of suitable tools for the task, mainly those employed for cutting and segmentation of different materials is of significant importance. Slight hand tools, mainly those powered by rechargeable batteries, facilitate the work, especially in areas where the access is difficult. Based on the experience in the dismantling of some old nuclear facilities of IPEN-CNEN/SP, some tools that would have facilitated the operations were identified and their availability could have improved the quality and efficiency of different individual tasks. In this paper, different cutting problems and techniques, as well as some available commercial hand tools, are presented as suggestion for future activities.Artigo IPEN-doc 21077 Use of dopants for thoria sintering temperature reduction - characterization of ThOsub(2)2015 - TAKIISHI, HIDETOSHI; GENOVA, LUIS A.; CAVALHEIRA, ELTON D.; COTRIM, MARYCEL B.; SANTOS, WILSON R.; LAINETTI, PAULO E.O.Artigo IPEN-doc 20546 Review of brazilian activities related to the thorium fuel cycle and production of thorium compounds at IPEN-CNEN/SP2014 - LAINETTI, PAULO E. de O.; FREITAS, ANTONIO A. de; MINDRISZ, ANA C.Artigo IPEN-doc 13964 Decommissioning of nuclear fuel cycle facilities in the IPEN-CNEN/SP2007 - LAINETTI, P.E.O.Artigo IPEN-doc 11015 Decomposicao termica de organoclorados por meio de oxidacao submersa em sais funcidos2004 - LAINETTI, P.E.O.; ABRAO, A.Artigo IPEN-doc 15590 Molten Salts as stripping media for radioactive superficial decontamination2010 - LAINETTI, PAULO E. de O.Artigo IPEN-doc 15591 Decommissiong aspects in the design phase of the brazilian multipurpose reactor - RMB2010 - LAINETTI, PAULO E. de O.Artigo IPEN-doc 19507 Review of brazilian activities related to the thorium fuel cycle and production of thorium compounds at IPEN-CNEN/SP2013 - LAINETTI, PAULO E.O.; FREITAS, ANTONIO A.; MINDRISZ, ANA C.