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[en] Ionizing radiation is currently employed in a variety of areas, including in health care. However, due to its potentially harmful characteristics to human health, an adequate and continuous monitoring is necessary, especially regarding personal dosimetry. In this context, conjugated materials in solution have been pointed out as promising systems for the design of dosimeters. Despite the interesting properties of these systems, most of them have low sensitivity, which restricts their effective application in real situations. The present work aims the development of dosimetric systems based on solutions containing conjugated materials. Two systems were evaluated: 1) based on poly [(9,9- dioctylfluorenyl-2,7,diyl)-co-(1,4-vinylienephenylene)] polymer in chloroform solution; and 2) aqueous solutions of Indigo-carmine dye, with and without zinc oxide nanoparticles or inorganic salt (NaCl). Samples with different concentrations were considered and different X-ray doses were employed. The dosimetric responses were evaluated by analyzing the optical absorption spectrum of the systems in the ultraviolet visible range and the vibrational spectrum. The results point out the F8PV/CHCl3 system as a promising dosimeter with optimized responses in relation to other similar polymeric systems, allowing the measurement of doses lower than 5 Gy. The results were interpreted considering the interaction between free radicals generated from solvent dissociation with the polymeric chains. Non-significant responses were obtained for Indigo-carmine based systems which reinforces the essential role of halogens in the dosimetric properties of conjugated materials in solutions. (author)
[en] Rare earth elements (REE) have become essential for our modern economy, in relation to the development of new energy and communication technologies. Depending on their technical economic efficiency and environmental footprint, hydrometallurgical processes enabling the recovery of separated elements could be of particular interest. Typically these processes include a first pre-treatment (crushing, milling and sieving) and an acidic leaching step (with eventual selective precipitation sub-steps), followed by a solvent extraction (SX) step aimed at the separation and purification of REE. Recently, diglycolamides (DGA) appeared as a very interesting group of extractants for the selective recovery of trivalent REE from nitric acid solutions, particularly in the presence of transition metal ions commonly found in various waste products. In this work, the TODGA extractant was successfully used for designing an efficient REE recovery process. The process integrates the mechanical and physico-chemical treatment of waste, followed by a solvent extraction step for the recovery and intra-separation of REE. Based on the experimental batch data, a phenomenological model has been elaborated taking into account the various distribution equilibria. The model has been implemented in our simulation code and used for calculation of various flowsheets, which have been tested at our pilot facility using compact continuous counter-current mixer-settlers. Experimental SX and modeling data allowing the recovery of >99.95% pure Dysprosium solution will be discussed in this paper. Preliminary technical-economic assessment and life-cycle analysis have also been conducted. Following this first successful demonstration, several novel dissymmetrical DGA have been developed and their solvent extraction behaviour in different acid media has been studied. Indeed, most processes use symmetrical DGA such as TODGA. The present work improves upon the classic design and demonstrates that novel dissymmetrical extractants display a remarkable improvement on REE extraction efficiency compared to reference TODGA in various acid media. Furthermore, the REE separation factors towards major impurities such as Fe3+ are substantially enhanced. The development of novel DGA with increased efficiency paves the way for the recovery and separation of high value REE from different streams. This opens new market opportunities since the effluent treatment has often an important impact either in the CAPEX or the OPEX of a solvent extraction plant. With some DGA extractants adapted to sulfuric acid media, the resulting effluent treatment plant could be cheaper than it would be using nitric acid media. Furthermore, their enhanced performance at low concentration should reduce the price of reagents in the OPEX. (author)
[en] This engineering academic work reports the development of a software for the costing support of quotation of studies, of supplies, of works and tests for people in charge of these tasks in the Marcoule Cogema centre. Based on working methods and approaches of the different people in charge of these assessments, on document organisation, on an analysis of information flows, of associated rules, and of existing data processing systems, the author discusses the system design life cycle, presents the costing method, the quotation costing support (support to quotation design, to return on experience, to quotation search, to quotation costing), presents the system functional analysis, and reports the development of the software prototype.
[fr]Le bureau d'etude Electricite, Automatisme et Instrumentation (EAI) a pour mission d'estimer les couts, le suivi de la realisation et la mise en service de travaux de type courant et de projets d'investissement sur des installations nucleaires. Ce service effectue l'ensemble des etudes conduisant a la realisation ou a la modification d'unites automatisees, d'electricite, de controle commande et d'instrumentation, au sein de la societe COGEMA sur le site de Marcoule. Quel que soit le type d'etude, un charge d'etude de ce service doit tout d'abord rediger un devis sur le cout de realisation des etudes, pour avoir l'accord de l'exploitant et pouvoir lancer les etudes. Les travaux sont suivis par la maitrise d'oeuvre (MOE) qui delegue un charge d'affaire specialise pour suivre la realisation dans son domaine de competence. Comme pour le charge d'etude, le charge d'affaire doit rediger un devis sur les couts de realisation de travaux, pour avoir l'accord de l'exploitant et pouvoir lancer les travaux. Actuellement les devis rediges par les charges d'etude et les charges d'affaire sont rediges manuellement, sans methode formalisee et homogene. Ces devis sont des devis engageants et les charges d'etude et d'affaire doivent pouvoir justifier a tout moment les ecarts entre le prevu, c'est a dire leur devis, et le realise, c'est a dire le cout total du projet une fois realise. Ce memoire a pour objet de realiser un outil informatique d'aide au chiffrage des devis d'etudes pour les charges d'etude, et des devis de fournitures, de travaux et d'essais pour les charges d'affaire. Pour mener a bien la realisation de cet outil informatique, mon travail aura pour objet: - d'analyser la facon de travailler des charges d'etude et des charges d'affaire, ainsi que l'organisation utilisee pour la circulation de documents; - d'analyser les besoins des utilisateurs et de la maitrise d'oeuvre; - de rediger une analyse fonctionnelle a partir du cahier des charges; - de definir une methode et une aide aux utilisateurs pour le chiffrage des devis d'etude; - de realiser une maquette limitee au chiffrage des devis d'etude dans un premier temps pour valider la faisabilite de cet outil informatique; - de realiser l'outil operationnel pour le chiffrage des devis d'etude, puis de l'etendre aux travaux et realisations. (auteur)
[en] The technical ability to decommission NPPs shut down after normal operation has been well demonstrated. However, concerns remain about the ability to accurately calculate and demonstrate the validity of decommissioning cost estimates, and to control costs during decommissioning. This paper describes recent international guidance on quality cost estimates for nuclear decommissioning projects and explores the potential added value that could be attained through more systematic analysis and reporting of decommissioning project costs. The OECD Nuclear Energy Agency (NEA) and the International Atomic Energy Agency (IAEA) have long been concerned about the need to promote greater transparency in decommissioning costing and have collaborated in a number of initiatives in pursuit of this objective. Together with the European Commission, they published 'The International Structure for Decommissioning Costing (ISDC)' in 2012. The ISDC provides a useful common reporting format for decommissioning costing. The NEA has also published guidance on the international peer reviews of decommissioning cost studies (2014) and on the practice of decommissioning cost estimation (2015). In September 2017, the NEA and IAEA published detailed guidance on addressing uncertainties in decommissioning cost estimates (the 'Addressing Uncertainties' report). This joint report sets out an approach to treating uncertainties reflecting current good practices in cost estimating. Specifically, it describes how uncertainties in decommissioning cost estimation can be addressed using standardized methods of estimating uncertainty and risk analysis. Its recommendations aim at enabling a consistent and comprehensive treatment of risk and uncertainty in the preparation of decommissioning cost estimates. Together these publications establish a good basis for producing comprehensive and high-quality cost estimates for nuclear decommissioning projects and for enhancing confidence in the estimates through improving transparency concerning the underpinning data and calculations, and more explicit representation of the uncertainties that may impact on project costs. There is increasing attention on understanding variations between cost estimates and apparent escalation of decommissioning costs. This arises both from the need to assure the adequacy of financing arrangements for future decommissioning projects and the ambition to improve the performance and ensure value-for-money in the delivery of decommissioning projects and services. A systematic analysis of actual decommissioning project costs in relation to the cost estimates would be expected to yield valuable insights about key cost drivers in actual decommissioning projects, and the extent to which current cost estimates accurately capture and reflect these. Aligning the reporting of decommissioning project costs with the underpinning cost estimates for the projects would also facilitate the identification of causes of major deviations between projected and actual costs. (authors)
[en] Canada completed the development of a reference concept of the Super-Critical Water-cooled Reactor (SCWR), which is designed to generate 1200 MWe. A continuation of the development is being pursued for a Super-Critical Water-cooled Small-Modular Reactor (SCWSMR) concept with a power output range of 120 to 300 MWe. This study uses a top-down cost estimation of the SCWSMR concept to produce two figures of merit: the total capital investment cost (TCIC), and the levelised unit energy cost (LUEC). The study estimates capital, operating and maintenance, fuel and decommissioning costs in calculating the TCIC and LUEC. Sensitivity analyses of these figures of merit with respect to the uncertainties in the assumptions were carried out to identify key factors affecting the estimates. (author)
[en] Full text: It is increasingly clear that building large nuclear plants represents a significant challenge in all countries and is especially difficult in liberalised electricity markets and where debt financing is required. However, when operating, nuclear plants provide essential system reliability, low carbon and resilience against shocks. This talk will explain how markets have developed to their current state and how they might be reformed to incentivise nuclear new build, while allowing the transition to more renewable sources. This relates both to ensuring price certainty and requisite financial returns to investors, while fully accounting for the system effects of current technologies. Following the discussion on markets, the talk will look at the interaction between market reform and construction finance, using examples from the UK and elsewhere. Finally, some ideas will be presented about what Australia needs to do if nuclear is ever to be successfully introduced. (author)
[en] Of all the quirky expressions that creep into our conversations, a personal favourite is 'throwing the baby out with the bathwater'. For anyone unfamiliar with the idiom, it means to discard something considered valuable or important while disposing of something that is thought to be worthless - such as an outdated idea or form of behaviour.
[en] Automatic translation: As in the previous quarterly report, the activities for work area I are based on the relevant titles of the framework work program (RAP), of which RAP 3 deals with the deadline situation. RAP 1: Preliminary Safety Report Not applicable in phase I of the project as a separate processing point. RAP 2: Costs / Profitability (HRB) To determine the cost of the HHT reference system and in preparation the cost / benefit analysis was essential groundwork carried out. You related to the creation of work packages to determine the costs of the various assemblies (BG) of the reference system with coordination with the responsible internal processors or external companies about the procedure and the underlying conditions, as well as the development of a computer program for the cost / benefit Analysis.
[de]Wie bereits im vorigen Quartalsbericht werden die Tätigkeiten zum Arbeitsbereich I nach den in Betracht kommenden Titeln des Rahmenarbeitsprogrammes (RAP) gegliedert aufgeführt, von denen RAP 3 auf die Terminsituation eingeht. RAP 1: Vorläufiger Sicherheitsbericht Entfällt in Phase I des Projektes als gesonderter Bearbeitungspunkt. RAP 2: Kosten/Wirtschaftlichkeit (HRB) Zur Kostenermittlung für die HHT-Referenzanlage und in Vorbereitung der Kosten/Nutzen-Analyse wurden wesentliche Grundlagenarbeiten durchgeführt. Sie bezogen sich auf die Erstellung von Arbeitspaketen zur Kostenermittlung der verschiedenen Baugruppen (BG) der Referenzanlage unter Abstimmung mit den zuständigen internen Bearbeitern bzw. externen Firmen über Vorgehensweise und zugrunde zu legende Randbedingungen, sowie die Ausarbeitung eines EDV-Programmes für die Kosten/Nutzen- Analyse.
[en] Interest in lithium for lithium-ion batteries for electric vehicles and other applications continues to drive interest in the extraction of lithium from various sources. Two sources already commercially exploited are lithium-bearing brines and hard rock deposits containing spodumene. A third source of lithium is lithium bearing clays. This paper presents a comparison of the extraction of lithium from clay against the extraction of lithium from spodumene. The chemistry is examined and process modelling is used to calculate reagent and utility consumption and costs for the two routes. The finding of this study is that the reagent/utility costs are very similar for the two routes. (author)