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The focus of the presented research is on the mechanical recycling of postconsumer plastics from Waste Electrical and Electronic Equipment (WEEE). Currently only a limited number of these plastics are mechanically recycled on an industrial scale while the majority is thermally treated for energy recovery. Since there is a significant potential for value recovery and to lower the environmental impact of plastics, the aim of this research is to develop new mechanical recycling processes based on the disassembly of plastic components and the sorting of these plastics based on identification by spectroscopic methods. This study will present this distinct recycling process based on a case study of the recycling of Acrylonitrile Butadiene Styrene terpolymer (ABS) from Liquid Crystal Display (LCD) TVs. The quality of the recyclates is evaluated by mechanical testing and injection molding of thin-walled products. Results showed that with direct reapplication of the obtained ABS without compounding, high mechanical properties could be achieved when compared to postshredder recycled ABS. However, remaining impurities in the polymer matrix limit the applicability of the recycled plastics to components without neither structurally critical nor aesthetical requirements., INTRODUCTION WEEE and ELV Waste Every year between 8 and 9 million tons of waste from Endof-Life Vehicles (ELV) and around 11.6 million tons of Waste Electrical and Electronic Equipment [...]

There have been increasing reports documenting barbiturate-related deaths, despite routine prescribing for only relatively rare indications. The aims of the current study were to examine trends in barbiturate-related deaths in Australia from 2000 to 2019 and determine the case characteristics and circumstances of barbiturate-related deaths. All barbiturate-related deaths identified in the Australian National Coronial Information System were examined. Information was collected on cause, manner, demographics, location, psychosocial factors, circumstances of deaths and toxicology. We examined these based on the age categories 18–44 years, 45–64 years and ≥65 years. We identified 511 cases. Mean age was 57.9 years (SD 20.2, range 18–100) and 56% were male. Intentional poisoning was the most common cause of death (87.5%) and was slightly higher in the oldest age group (92.1%) and lowest in the youngest age group (81.1%). Pentobarbitone was the most common barbiturate (75.7%) and pentobarbitone-related deaths increased from 0% in 2000 to 93.6% in 2017. There were notable differences between age categories, with the youngest age group recording more severe psychiatric histories. In contrast, the oldest age group were more likely to have severe physical health problems, such as cancer, chronic non-cancer pain, neurological conditions and significant cardiopulmonary morbidity. Euthanasia resources were commonly documented (33.9%), most frequently in the oldest age group (52.3%). Barbiturate-related deaths in Australia are increasing, particularly pentobarbitone-related deaths. Most deaths were intentional and involved adults across the lifespan. Younger people were more likely to have significant mental health problems, whilst the oldest age group were more likely to have severe physical health conditions. [ABSTRACT FROM AUTHOR]

To make disassembly cost-efficient, one-to-many fasteners are needed. These so-called active fasteners use advanced materials or structures as a catalyst for disassembly, allowing multiple assemblies to separate simultaneously after exposure to specific external triggering conditions. Using topology optimization this paper explores the alternative configurations of pressure-based active fasteners. The optimization problem is first solved in the 2D space for a snap-fit like design. Based on these results the problem was extended to 3D and solved. Similar as for the 2D results, a detailed finite element verification was conducted which proved the optimized structure shows an increase of the disassembly efficiency with 200-250% compared to the initial non-optimized structure measured in displacement of the snapping features. As such, this paper shows that for future manufacturing businesses, active fasteners promise to be a valid alternative for shredding. Since the model can easily be modified for other trigger conditions or design configurations, the proposed approach proves to be suitable to develop different types of one-to-many disassembly fasteners. [ABSTRACT FROM AUTHOR]

This paper discusses the planning module of system that has been developed in a research project investigating the possibilities for automatic planning of press brakes. Only limited attention has been given to production-planning problems for bending processes in the sheet-metal industry. A well-considered production-planning module provides an important opportunity for cost saving and flow-time reduction. The module will support and may replace an experienced planner. Under certain assumptions, the planning problem can be modelled both ways as a Travelling Purchaser Problem (TPP) and as a Generalized Travelling Salesperson Problem (GTSP). A hierarchical decomposition approach is presented to solve the TPP, while the GTSP is solved using guided local search (GLS). These methods are compared based on a set of problems from a real production environment and perform well. [ABSTRACT FROM AUTHOR]

It is widely recognized that disassembly-based product End-of-Life strategies, such as component reuse or simple fraction material recycling, are environmentally beneficial. However, current disassembly costs hinder a widespread application of these strategies. This paper quantifies the disassembly time reductions required to achieve economic feasibility of systematic product disassembly. A modelling framework, based on linear programming, is used to investigate the effect of reducing the expected disassembly time and cost on the selection of the optimal End-of-Life strategy. The problem is optimized from an End-of-Life treatment facility point of view. All findings are based on the Belgian cost and price information captured in spring 2004. The linear programming model shows that for small products from the Waste of Electric and Electrical Equipment (WEEE) category disassembly-based End-of-Life strategies will hardly become optimal, while for medium- and large-sized products, this scenario can be made optimal if a substantial disassembly time reduction is achieved. Possible strategies to realize such reduction are briefly sketched. [ABSTRACT FROM AUTHOR]

The sequencing of part set-ups, in the context of design verification or process planning activities for sheet metal bending operations, is a rather complex combinatorial problem. The verification of the feasibility and the acceptability of a single bend set-up requires CPU-time consuming operations, e.g. collision checking and a manipulation requirement analysis. For more complex parts, and thus increased numbers of bends, exhaustive search methods can therefore not be applied in a time-economic way. Although the identification of an optimal sequence may not always be possible, a number of techniques can be applied to significantly downscale the problem size. Several complementary approaches have been worked out to proceed in identifying near-optimum feasible bend sequences. Constraint solving and branch-and-bound techniques are used to identify interesting potential solutions. The reported branch-and-bound search method is characterized by a dynamically updated penalty system, that reflects the manufacturing knowledge obtained through analysis of partial sequences. A case study is used to illustrate the effectiveness of the applied search procedures. [ABSTRACT FROM AUTHOR]