This thesis aims at developing a (dis/re)assembly oriented methodology towards product end-of-life. Particular focus in this thesis is on the circularity of furniture via design for (dis/re)assembly. The main motivation behind this study was the need for a method to evaluate the (dis/re)assembly options of furniture designs to be able to facilitate repair, reuse, remanufacturing, refurbishing, or recycling. The study draws upon relevant theories and prior research on Circular product Design, Design for EoL, Design for Environment, and Design for (Dis)assembly of vehicles, electrical and elocronic equipments, whitegoods, as well as office furniture, though relatively limited. The proposed methodology determines major aspects of design for (dis/re)assembly to be taken in to consideration in the early stages of product development. It further provides a set of parameters that are relevant to cabinet type and upholstery furniture group. The study involves a variety of qualitative research methods that are embedded in an interactive research conduct with the engagement of different stakeholders that are charged with the task of product development at Ikea of Sweden (IoS), the collaborator of this study.  The proposed methodology is implemented on three selected furniture designs in a pilot study. The results of the study, above all, suggest that (dis/re)assemblability of a product is a strategic choice that needs to be made at early phases of product development, namely the design phase. Two particular features of the furniture groups, upon which this study focuses, emerges as factors having negative impact on the disassemblability of products: first, wooden frame sofas with respect to their complex structure and connectivity of componants and, second, permanent joints with respect to their destructive impact on the product. The study concludes that it is feasible to develop and implement a potentially comprehensible method to evaluate the ease of disassembly of furniture products and to design for disassembly. The proposed methodology in this study is a contribution to support product design for disassembly towards product circularity.

Returned products of many industries are transported backwards through supply chains for recovery, thus forming &ldquo / closed-loop supply chains&rdquo / . Benefits, forthcoming with more effective management of recovery of returns are gaining importance. However, some issues, such as lack of information required to assess the quality of the returned products, may translate into critical uncertainties in the product recovery decisions and prevent closed-loop supply chains from operating efficiently. Hence, it is envisaged that significant economies may be attained by increasing the quantity of information fed into the planning decisions related to returned products. Thus, the objective of this study is to test the hypothesis that ready availability of perfect quality grade information associated with returned products by means of &ldquo / embedded systems&rdquo / , may lead to improved over all performance of recovery operations. To this end, in this thesis, linear programming models of generic multistage recovery processes are built. It is demonstrated by computational studies that significant gains may be obtained especially in environments where the prices of recovered products are decreasing in time.

The furniture industry is a thriving industry in the past decades all over the world. The increase in production and sales of furniture products means that more raw materials are needed and more furniture waste is produced at the same time. Taking into account the unsolved environmental issues, it is necessary to make innovation changes to reduce the waste and overcome the continuously increasing resource consumption. Circular economy draws a wide attention under this situation. As an alternative to replace the traditional linear consumption model, it balances the economic development and environmental concern. Turning waste into a new resource is a profitable opportunity for the furniture industry. However, product recovery in this industry meets obstacles due to the character of the furniture.This study considers discarded bulky furniture products. It focuses on the first step of furniture waste recovery: the collection process. The aim of this research is improving the efficiency of a “many to one” collection process in a reverse logistics system and increasing the recovery level within the hierarchy of options for discarded furniture. By using the soft system methodology, this study explores the current discarded furniture collection situation within Europe and then analyzes each essential element of this collection system. After that, combining with the relevant circular economy theory and information gathered from a case furniture company, we design a new conceptual business process model for discarded furniture collection.In the newly designed model, the collection process is carried out by the individual transport option with sufficient capacity from customer’s home to the furniture store. The new model is based on a collaborative lifestyle information platform. By managing the real-time information, the platform aligns individuals’ transport resources with discarded furniture demand to reduce the transport cost of the collection process. This model aims for optimal use of the available individual resources to complement the transport process. Moreover, this information platform helps to collect information in the early stage to reduce the uncertainty of reverse logistics.

The objective of this work is to evaluate the reaction initiation characteristics of quasi-statically compressed intermetallic-forming aluminum-based reactive materials upon impact initiation, consisting of equi-volumetric tantalum-aluminum, tungsten-aluminum, nickel-aluminum, and pure aluminum. A modified Taylor rod-on-anvil setup was employed to determine the reaction initiation threshold kinetic energy and actual energy for plastic deformation and subsequent reaction. Experimental sample remnants were recovered and examined through X-ray diffraction to determine reaction products.The overall results indicate that of the various intermetallic-forming systems investigated, Ta+Al was the most reactive and was the only system where any reaction products were retrieved. While all of the intermetallic systems reacted in air, only Ta+Al and W+Al reacted in vacuum environment suggesting differences in reaction mechanisms influencing the reactivity of intermetallic mixtures. Based on the threshold energy for onset of reaction it appears that the Ta-Al compacts show reaction conditions below those required for reaction of Al in air. This combined with the fact that Ta+Al compacts also react in vacuum implies that the Ta+Al undergoes anaerobic intermetallic reaction while the other systems react with the oxidation of Al. The effect of compact packing density on the kinetic energy threshold for reaction initiation were also evaluated. It was observed more densely packed Ta+Al and Ni+Al powder compacts react more easily than less densely packed samples. While the effect of packing density is not as obvious in the case of pure Al and W+Al powder compacts. Finally, a particle size effect is seen on Ni+Al on samples of < 92% density where coarser (+325 -200 mesh) equal-volumetric powder mixtures were observed to be more reactive than finer Ni+Al (-325 mesh).

Les milieux biologiques bruts, provenant des opérations de transformation de biomasse sont souvent caractérisés à la fois par leur caractère polluant et par un potentiel de valorisation important. Le développement de procédés adaptés au traitement de tels milieux complexes présente ainsi beaucoup d’intérêt. Les jus verts générés par la déshydratation de la luzerne (Medicago Sativa) sont caractérisés par une forte teneur en protéines. Outre leur valeur nutritionnelle importante, ces protéines ont des applications potentielles dans plusieurs domaines, notamment environnemental de part leur teneur élevée en Ribulose 1,5 Bisphosphate Carboxylase Oxydase (Rubisco), enzyme responsable de la fixation du CO2 chez les plantes. Dans ce travail la séparation sélective de la Rubisco à partir du jus de luzerne industriel centrifugé par chromatographie d’échange d’ions a été étudiée. Dans un premier temps une méthode d’analyse qualitative et quantitative a été mise au point pour la détection et la quantification de la Rubisco en solution et ainsi le suivi du procédé de séparation. Dans un deuxième temps, le procédé de séparation a été étudié en colonne, en lit fixe et en lit expansé, en utilisant le support échangeur d’anions Q Hyper Z et l’effet de la dilution du milieu sur la capacité dynamique du procédé a été analysé dans les deux cas. Les résultats obtenus ont montré que les deux modes de contact permettent d’avoir des capacités dynamiques de rétention du même ordre de grandeur que celles de la littérature. Après élution, la Rubisco a été concentrée jusqu’à 21 fois et les fractions produites étaient caractérisées par un grand degré de pureté. Par ailleurs, des études d’équilibre et cinétique d’échange ont été initiées dans ce travail et ont démontré que malgré la taille importante de la protéine d’intérêt (560 kDa) les limitations stériques à son transfert ne sont pas plus importantes que dans le cas de protéines plus simples et plus petites et que le support Q Hyper Z présente effectivement une grande affinité pour la protéine. Enfin une première approche théorique a été conduite pour la compréhension des interactions entre la protéine et l’échangeur dans ce milieu complexe. Elle a permis de confirmer l’importance de la prise en compte de la présence d’autres biomolécules dans le milieu sur la rétention de la Rubisco, peut être même plus que celle des sels / Biological raw material derived from bio-refinery processes, is often considered a source of pollution but it seems also to be a promising alternative to potential material recovery. The development of suitable processes for handling such complex biological material has so many concerns. Green juice produced from mechanical dehydration of Alfalfa (Medicago sativa) is an excellent source of protein with high nutritional quality. Ribulose-1,5-bisphosphate carboxylase oxygenase (Rubisco) is the most abundant protein in the green juice, with potential applications in many fields, such as human nutrition, pharmaceuticals, environmental… The aim of this study is to isolate and recover Rubisco produced from an industrial alfalfa green juice, by ion exchange chromatography process. First of all, a qualitative and quantitative analytical method was developed to provide reliable information about Rubisco content monitoring in the separation process. In a second step, the separation process was performed in fixed and expanded bed, using the anion exchanger Q Hyper Z. In both cases, the effect of the dilution of the green juice on the dynamic capacity of the columns was studied. The results showed that the dynamic capacity retention was similar in both columns to those reported in literature. After elution step, Rubisco was concentrated 21 times and produced with high level of purity. Furthermore, kinetic of ion exchange study was initiated. Despite the large size of the protein (560 kDa), steric limitations to mass transfer were not very significant when compared to those of conventional small proteins. The support Q Hyper Z showed an excellent affinity for the protein recovery. Finally, a first theoretical investigation has been conducted for understanding the retention mechanism between the protein and the separation column. This study shows the importance of taking into account the presence of other bio-molecules in order to perform the retention of Rubisco, perhaps even more than that of salts

Les travaux présentés dans ce manuscrit portent sur la conception des lignes de désassemblageen contexte incertain. Une ligne de désassemblage consiste en unesuccession de postes de travail où les tâches sont exécutées séquentiellement au niveau de chaque poste. La conception d'un tel système, de revalorisationdes produits en fin de vie, peut être ramenée à un problème d'optimisation combinatoire.Ce dernier cherche à obtenir une configuration permettant d'optimiser certains objectifs enrespectant des contraintes techniques, économiques et écologiques.Dans un premier temps, nous décrivons les activités principales de la revalorisation des produitsen fin de vie, en particulier le désassemblage. Puis, après présentation des travaux de la littératureportant sur la prise en compte des incertitudes des durées opératoires lors de la conception des lignesde production, nous nous focalisons sur l'étude des incertitudes des durées opératoires des tâches de désassemblage.Ainsi, nous présentons trois modélisations principales avec leurs approches de résolution.La première s'intéresse à la minimisation des arrêts de la ligne causés par les incertitudes des durées des opérationsde désassemblage. La deuxième cherche à garantir un niveau opérationnel de la ligne lié à sa cadence de fonctionnement.Le but de la troisième modélisation est l'intégration des problématiques de conception des ligneset de séquencement des tâches de désassemblage. Enfin, les performances des méthodes de résolutionproposées sont présentées en analysant les résultats d'optimisation sur un ensemble d'instances de taille industrielle. / This thesis is dedicated to the problem of disassembly line design in uncertain context. A disassembly linecan be represented as a succession of workstations where tasks are performed sequentially at each workstation.The design of such a product recovery system can be reduced to a combinatorial optimization problem which seeksa line configuration that optimizes certain objectives under technical, economical and environmental constraints.We begin by describing the principal product recovery activities especially disassembly. Then, after a literaturereview on the design of production lines under uncertainty of task processing times, we focus our study on the consideration of the disassembly task time uncertainties. Hence, we present three main models as well as the associatedsolution approaches. The first one is interested in minimizing the line stoppages caused by the task processing timeuncertainties. The second one seeks to guarantee an operational level closely related with the line speed. The goal of thethird model is to integrate the line design and sequencing problems. At last, the performances of the proposed solutionapproaches are presented by analyzing the optimization results on a set of instances of industrial size.

Enforcing EoL recovery strategies is critical to shifting the paradigm from a linear to a circular economy that enables future growth. This study identifies relevant evaluation indicators for End of-life recovery strategies in the Outdoor Power Equipment industry, as well as the drivers and barriers to implementation of End-of-life recovery strategies. Furthermore, it contributes to the United Nations Sustainable Development Goals 8 and 12 and serves as a starting point for increasing product circularity in the Outdoor Power Equipment industry through End-of-life recovery strategies. For this purpose, a structured literature review and an exploratory case study was conducted in collaboration with the market leader, Husqvarna Group. The results showed the relevant evaluation indicators selected by the case company, addressing the three sustainability dimensions. From an organizational perspective, this study emphasizes the role of different factors acting as drivers and barriers to EoL recovery strategy implementation for industry to drive a successful implementation. / Att genomdriva cirkulära produktstrategier är avgörande för omställningen till cirkulär ekonomi, vilket möjliggör framtida ekonomisk tillväxt. Den här studien identifierar relevanta utvärderingsindikatorer för cirkulära produktstrategier inom tillverkningsindustrin, samt drivkrafter och barriärer för genomförande av dessa. Studien bidrar till Förenade Nationerna Globala Mål för Hållbar Utveckling 8 och 12 och fungerar som en utgångspunkt för att öka livslängden för produkter och komponenter inom industrin. För detta genomfördes en explorativ fallstudie genom en strukturerad litteraturgenomgång, workshops och intervjuer i samarbete med marknadsledaren Husqvarna Group. Resultaten visade att relevanta utvärderings indikatorer är klimatpåverkan, kundnöjdhet och intäktspotential, som tar upp de tre hållbarhetsdimensionerna. Från ett organisatoriskt perspektiv betonar denna studie barriärer mellan affärsutveckling och organisation, vilket hotar framgångsrik implementering. För att driva en framgångsrik implementering, är anpassat resultatmål, utbildning och ökad teknisk kapacitet sätt att övervinna den nuvarande verkligheten.

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