Recycling of Mixed Plastics Waste

Section 3 discusses options for feedstock recycling of mixed plastic waste ... 

Concerning feedstock recycling of mixed plastic waste (MPW) with a low chlorine content, the following initiatives seem to be most promising. They are either operating in practice, have operated in the past, or have a fair chance of becoming operational in the short-term. Methods include ... 

Feedstock recycling is examined as a method of plastics recovery. The range of techno logics currently employed are described, and include pyrolysis, hydrogenation, gasification, and chemolysis. Methods for the recycling of mixed plastics wastes are discussed, which include work by BP Chemicals, VEBA Oil, Shell Chemicals and Leunawerke. 

Tall S (2000) Recycling of mixed plastic waste—Is separation worthwhile PhD Thesis, Royal Institute of Technology, Stockholm, Sweden... 

TECHNOLOGIES FOR TERTIARY RECYCLING OF MIXED PLASTIC WASTE (MPW)... 

Adhesion of thermodynamically incompatible polymers is of current interest because of its implications for developing new multiphase polymer materials and for recycling of mixed plastic wastes. Many elegant experiments have been reported in which various types of copolymer are introduced at the interface as putative compatibilizers. The interface may be strengthened as a result of interdiffusion and roughening on a nanoscale. 

This chapter will analyze the application of mechanical recycling technologies to polymer blends, describing the use of recycled materials as a blend s secmid component or the direct recycling of mixed plastic waste. 

Recycling of mixed plastics waste is very difficult, in particular because of the incompatibility of different pol3rmers and danger of degradation of polymers, such as PVC, but also due to their different melting points. 

The possibility of recycling of mixed plastics waste without any compatibilizer and obtaining a recycled material which easily processed in conventional machinery add value to manufacture. The properties of resultant material are also essential. 

Dubrulle D Orhcel, B. (1996) New Process for Recycling of Mixed Plastics Waste, in... 

Recycling of mixed plastics waste is not new. The first industrial applications in Japan date from 1973. It is well known that it is possible to manufacture rods, stakes, bars, boards, plates, etc. from mixed plastics waste but the mechanical properties of these products are inferior. The recycled products cannot compete with virgin plastic materials, and therefore they have to find their market in areas dominated by cheap materials like wood and concrete. Moreover, the market of park benches, playgrounds, fences, etc. cannot absorb, in the long run, the massive amounts of plastic wastes that are produced every year. 

The maj or problems in recycling of mixed plastic waste are due to their inferior processability, which results in materials having poor mechanical properties. La Mantia et al. and Vezzoli et al. present experimental results which disclose the possibility of obtaining recycled materials with acceptable properties from mixed plastic waste. 

An alternative method of recycling of mixed plastic waste is based on a separation of different components into homogeneous fractions. Sereni describes opportunities in this area and interesting industrial equipment required for effective separation of PET and PVC. 

Mechanical recycling of mixed plastics wastes is an even more contentious issue due to the poor mechanical properties and durability of blends of mixed plastics [10,11]. The first can be overcome to some extent by using expensive solid phase dispersants ( compatibilizers ) but most recyclers of mixed plastics cannot afford to use this technology and instead rely on thick sections of the recycled product to provide acceptable mechanical performance (e.g. as wood substitutes for park benches, docks, road signs, etc). However, it has been shown in a critical study of the Duales... 

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