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The separation process within a mechanical recycling plant plays a major role in the context of the production of high-quality secondary raw materials and the reduction of extensive waste disposal in landfills. Traditional plants for plastic separation employ dry or wet processes that rely on the different physical properties among the polymers. The hydraulic separator is a device employing a wet technology for particle separation. It allows the separation of two-polymer mixtures into two products, one collected within the instrument and the other one expelled through its outlet ducts. Apparatus performance were analyzed as a function of fluid and solid flow rates, flow patterns developing within the apparatus, in addition to the density, shape, and size of the polymers. For the hydraulic configurations tested, a two-way coupling takes place where the fluid exerts an influence on the plastic particles and the opposite occurs too. The interaction between the solid and liquid phases determines whether a certain polymer settles within the device or is expelled from the apparatus. Tests carried out with samples of increasing volumes of solid particles demonstrate that there are no significant differences in the apparatus effectiveness as far as a two-way interaction takes place. Almost pure concentrates of Polyethylene Terephthalate (PET), Polyvinyl Chloride (PVC), and Polycarbonate (PC) can be obtained from a mixture of traditional polymers. Tests conducted on Polylactic Acid (PLA) and Mater-Bi® samples showed that the hydraulic separator can be effectively employed to separate bio-plastics from conventional plastics with remarkable grade and recovery.

ERECON (2014) Strengthening the European rare earths supply chain: Challengesand policy options. Kooroshy, J., G. Tiess, A. Tukker, and A. Walton (eds.).; Policy recommendations:1.Maintaining and strengthening the European Rare Earth Elements (REE) skills and knowledge base through research funding, science and technology education and international cooperation.Without cutting-edge research and technical expertise, a European high-tech REE industry cannot flourish. The EC and Member States should support funding for research grants, scholarships, and training networks, and enhance European and international cooperation through coordinated calls, researcher exchanges, and joint high-level conferences.2.Creating the basis for informed decision-making on REEs through a European Critical Materials Observatory.Mapping and monitoring of REE supply chains is necessary for informed decision-making. Expertise in Europe could be pooled in a virtual Critical Materials Observatory that provides the public with consistent and authoritative knowledge on REEs (e.g., information on advanced exploration projects, prices, key demand and supply trends, and the urban mine potential).3.Support promising technologies through funding industry-led pilot plants for innovative HREE processing.The EC, industry and Member States should accelerate the commercialization and scaling up of key technologies through co-financing industry-led pilot plants. This should include pilots for REE recovery from heavy rare earths-rich minerals, direct-alloy recycling routes, process and sensor equipment for REE recycling, and REE recovery from industrial residues.4.Levelling the playing field for European HREE exploration through co-funding for prefeasibility and bankable feasibility studies.Support from federal and state governments in the U.S., Australia and Canada has played a critical role in advancing project exploration. The EC and Member States should evaluate possibilities for supporting the extensive R&D necessary for pre-feasibility and bankable feasibility studies, to avoid high quality deposits in Europe simply going unexplored.5.Making waste management REE-friendly through eco-design, incentive schemes for collecting priority waste products, and streamlining policy and waste regulation.The EC and Member States should promote recycling-friendly design to help identify and recover REE components in waste more easily. Potential incentives for stimulating REE waste collection should be evaluated and the shipment of REE wastes should be facilitated. More consistency should also be created in implementing and applying existing waste regulations.6.Boost supply security and de-risk strategic REE investment cases through enhanced cooperation among European end-users and other stakeholders.Leading end-users should engage in strategic cooperation across industry and with governments. This could include setting up a voluntary European ‘critical raw materials fund’, establishing a ‘European Resource Alliance’ similar to the German Rohstoffallianz, and convening a high-level taskforce to examine ways in which public funding could support resilient REE supply chains for Europe.

Recovery of useable plastics from post-consumer and manufacturing waste remains a major recycling challenge. The global consumption of plastics was reported to be 230 million tonnes in 2005 (PlasticsEurope 2007a) of which 47.5 million tonnes were produced in Europe (25 European Union countries + Norway and Switzerland). Of the European production, only 22 million tonnes were reported as having been collected. Of this collected waste, 4 million tonnes were recycled as a manufacturing feedstock (18%) and 6.4 million tonnes went into energy recovery (29%), with the balance (11.6 million tonnes) probably being disposed in landfills (PlasticsEurope 2007b). The recycling of plastics is a process essential to reduce the efflux of materials to landfills and to decrease the production of raw materials. In recent years awareness of the importance of environmental protection has led to the development of different techniques for plastic recycling. One issue related to the recycling of this material is the presence in the market of many types of plastics (polymers with additives), often with similar characteristics that make them difficult to differentiate in the recovery phase. The separator “Multidune” is a hydraulic separator by density. Its name derives from the characteristic undulate profile of the channel where separation occurs. The channel is constructed from a sequence of closed parallel cylindrical tubes welded together in plane which are then sliced down the lateral mid-plane and the lower complex is laterally shifted relative to the upper complex. The Multidune allows solid particle separation according to their specific weight and the velocity field establishing within the apparatus. Previous investigations (De Sena et al., 2008; Moroni et al. 2008) suggested the flow within the Multidune is organized into three main patterns. Principally, a longitudinal transport flow takes place, where the velocity is high. A particle belonging to this region can move from one camera to another. The second region is the lower recirculation zone with high values of the vorticity field. Particles belonging to this region undergo the vertical impulse of the fluid. The thrust is proportional to the vertical velocity component and, in conjunction with gravity and buoyancy, determines the destiny of a particle. If the thrust is larger than the net weight of the particle, an interaction with the principal transport flow occurs and, consequently, the particle will move to the following chamber. The third region is the upper recirculation zone whose dimensions are smaller than the other recirculation zone. If a

Hazardous waste management should fulfil the following three main goals: (i) to protect human health and the environment, (ii) to reduce waste while conserving energy and natural resources and (iii) to reduce or eliminate the volume of waste to dispose of. The last two of these goals may derive from recycling, which aims at reducing raw materials and energy consumption and decreasing the volume of waste materials that must be treated and disposed of.

The recovery of high-quality plastic materials is becoming an increasingly challenging issue for the recycling sector. Technologies for plastic recycling have to guarantee high-quality secondary raw material, complying with specific standards, for use in industrial applications. The variability in waste plastics does not always correspond to evident differences in physical characteristics, making traditional methodologies ineffective for plastic separation. The Multidune separator is a hydraulic channel allowing the sorting of solid particles on the basis of differential transport mechanisms by generating particular fluid dynamic conditions due to its geometric configuration and operational settings. In this paper, the fluid dynamic conditions were investigated by an image analysis technique, allowing the reconstruction of velocity fields generated inside the Multidune, considering two different geometric configurations of the device, Configuration A and Configuration B. Furthermore, tests on mono- and bi-material samples were completed with varying operational conditions under both configurations. In both series of experiments, the bi-material samples were composed of differing proportions (85% vs. 15%) to simulate real conditions in an industrial plant for the purifying of a useful fraction from a contaminating fraction. The separation results were evaluated in terms of grade and recovery of the useful fraction.

A new approach is suggested for the purposes of obtaining a proper character-distribution pattern of a particle set. Different methods of modeling the series of size characterization data are examined. Fourier analysis is applied to detail new parameters (features) for enhancing the differences between size distributions under different comminution operating conditions. Size distribution relating to a set of comminuted particles is processed as a signal (size vector) to extract the feature set. The results are compared to provide an insight into the effectiveness of each data analysis method. In particular, some of the Fourier series sine-coefficient values, relating to the size vector of a particle set, can represent the post-comminution size-distribution pattern. For example, size distribution following cryogenic comminution under different temperature conditions can be modeled using a second-order equation function of four selected Fourier analysis sine coefficients.

Minimisation of waste to landfilling is recognised as a priority in waste management by European rules. In order to achieve this goal, developing suitable technologies for waste recycling is therefore of great importance. To achieve this aim the technologies utilised for mineral processing can be taken into consideration to develop recycling systems. In particular comminution and separation processes can be adopted to recover valuable materials from composite waste. In this work the possibility of recycling pharmaceutical blister packaging has been investigated. A suitable comminution process has been applied in order to obtain the liberation of the plastic and aluminium components. Experiments of electrical separation have been carried out in order to point out the influence of the process parameters on the selections of the different materials and to set up the optimum operating conditions.

The exponential growth of photovoltaic (PV) installations highlights the necessity to cope with the environmental impacts which could raise from wrong practices for disposal of end-of-life PV modules. In fact, their possible disposal in landfills would represent a loss of materials and energy, as PV modules are goods that can become very useful even at the end of their life. In order to improve the valorisation of waste coming from end-of-life PV modules and of materials they contain, high value recycling processes are needed. These solutions differ from other end-of-life management alternatives, that are generally more simple and economical, like for example the treatment of the PV modules in a recycling plant for laminated glass or their disposal at a landfill after the recovery of the aluminium frame and a pre-treatment in a municipal incineration plant. All these low value approaches have in common the loss of valuable resources, represented by high value materials and components contained in PV modules (wafer/silicon, indium, tellurium and so on), which inevitably would end their life cycle in a landfill, without being adequately recovered. Differently, some separation and treatment processes have been recently developed, adopting machines and also plants deriving from traditional mineral processing, which allow recovering and recycling of precious metals and materials.