Mechanical recycling, feedstock

This article presents details of the gloomy picture of the environmental impacts associated with PVC waste which has been painted by four PVC waste management studies carried out for the European Commission. The studies cover mechanical recycling, feedstock recycling, behaviour in landfill, and the influence of PVC on incinerator flue gas cleaning residues. 

Mechanical recycling, feedstock recycling and thermal energy recovery are all valid methods of recycling plastics. This is the conclusion reached by an ecobalance study coordinated by the TUV Rheinland. According to this study, a mixture of all three recycling methods provides... 

A material is reclaimable when both a treatment technology and a market for the resulting new material are available [3]. This book concentrates on the reclamation and recycling of plastics. There are several options for how this can be done reuse, mechanical recycling, feedstock recycling and energy recovery. These are defined next. 

Finally, other relevant treatment options for plastics waste include landfill and mechanical recycling. Since these options (unlike Vinyloop and cement kiln incineration) are not even similar to feedstock recycling we discuss them here only very briefly. Mechanical recycling of plastics (be it PVC or other plastics), needs dedicated collection of the plastic waste in question. This is only possible for selected plastic flows (high volumes, recognisable products, products consisting mainly of one plastic). Landfill can accept plastic waste in any waste context (pure plastic type, MPW, mixed materials). I will only address the costs of these alternative technologies. 

The Parak process for the recycling of polyolefins and the production of raw materials for the production of paraffin waxes, is described. The process is claimed to provide a link between mechanical and feedstock recycling, employing elements of feedstock recycling, e.g. melting and cracking. The main product obtained is paraffin wax, which can be used for coatings for cardboard and paper, and corrosion protection. 

Post-consumer plastic waste recycling is discussed with special reference to feedstock recycling, the advantages it has over mechanical recycling, and the techniques involved. Chemolysis and thermolysis are explained, and... 

This paper explores the use of plastics in cars to make them more environmentally friendly. It lists major environmental issues. It then discusses in detail the positive role of plastics during the lifetime of a car (more plastics means less fuel consumption), the fact that automotive plastic parts are user-friendly and safe, the current and future uses of plastics in cars, recovery options for plastics in end-of-life vehicles, mechanical recycling (which is the best recovery option for many large automotive parts), energy recovery (the solution for small plastic parts), and feedstock (or chemical) recycling. Lastly, the way forward is considered. 

Besides mechanical recycling, the conversion of waste plastics into a petrochemical feedstock is another way for the recovery of the organic materials from a polymer waste. A basic problem is the removal of organobromine compounds. 

Despite the evidence that PVC recycling initiatives were increasing and approaching commercial viability, the political pressure on PVC continued in the late 1990s viz. the EU automotive End-of-Life Directive (418) and EU waste management studies on mechanical and feedstock recycling (282). 

Feedstock or chemical recycling is seen as complimentary to mechanical recycling and seems appropriate for cost effective treatment of mixed and contaminated plastic waste streams (115). A progress report, on potential technologies for high PVC content mixed plastic waste streams, is available (21). Promising developments, which look technically and economically viable, are ... 

This report discusses the options for feedstock recycling of plastics waste, including aspects of the environmental and economic pros and cons relating to feedstock recycling in comparison with incineration or mechanical recycling of municipal solid waste, based on a number of life cycle assessments. Particular reference is made to the experience of the TNO-CML Centre of Chain Analysis.485 refs. 

In the frame of Vinyl 2010 [26] the PVC Industry in the European Union made a number of voluntary commitments, regarding the control of emissions from VCM-producing plant, the phasing out of cadmium (both already realized) and lead-based stabilizers (to be completed by 2015) and the voluntary recycling of 200 000 tonnes per year by 2010. Some projects allow for mechanical recycling (Solvay s Vinyloop, at Ferrara), but feedstock recycling is also being considered [26]. 

Feedstock recycling is complementary to mechanical recycling since it is less sensitive to nnsorted or contaminated plastics waste and enlarges the overall recycling capacities for large waste qnantities to be snpplied in the future. Examples of such mixed streams are... 

F. Perugini, U. Arena and M. L. Mastellone, A life cycle assessment of mechanical and feedstock recycling options for management of plastic packaging wastes, Env. Progress, 24(2), 137-154 (2005). 

A study by the Association of Plastics Manufacturers in Europe (APME) assessed the environmental impacts of mechanical and feedstock recycling and energy recovery of waste plastics. It was compared in terms of consumption of resomces and environmental emission pollution potential. The criteria of consumption of energetically exploitable resources and contribution to the greenhouse effect lead to the following order of preference for feedstock recycling and energy recovery processes ... 

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