Plastics Mechanical Recycling Process

Netherlands (high ground water level, soft soil), a price of some 50 per tonne is enough to realise a controlled landfill (including aftercare systems). The gate fee of mechanical recycling processes depends very much on the type of plastic and type of mechanical recycling and cannot be specified here. 

In the future, feedstock recycling of mixed plastics to synthesis gas, petrochemical feedstocks, coal and coke replacements, and monomers has the potential to complement mechanical recycling processes at a significant scale worldwide. Many of the plastic feedstock recycling processes appear to be technically feasible and robust enough to warrant further development. Much more needs to be understood about infrastructure requirements, feedstock quality requirements, processing, and economics. 

Secondary or mechanical recycling processes differ from tertiary or feedstock recycling and quaternary or energy recovery processes principally in the potential to retain some of the energy used from plastics production, and in general terms provide for financially advantageous options. 

Fractions of plastics waste which are not possible or not meaningful to recycle in material (mechanical) recycling processes are used in blast furnace or recycled in feedstock (chemical) recycling. Here hydrogenation has the priority followed by gasification and pyrolysis. Pyrolysis of type clean plastics waste will be suited only in exceptional cases. 

A mechanical recycling process suitable for mixed plastics, where molten materials are fed into simple moulds. 

Polymer waste has been increasing at city landfills tremendously [1]. Thus the best solution in overcoming the buildup of plastic solid waste is recycling. The demand for recycling has increased further, especially for expensive engineering resins such as polyamide (PA-6), because it possesses a lot of excellent properties. Previous studies have shown that unmodified PA-6s are excellently suitable for utilization in mechanical recycling processes [2]. 

This article provides brief information from a study carried out in the Netherlands, which revealed that combustion with energy recovery is the most economical way of processing waste plastics, whilst mechanical recycling is the most environmentally attractive option. 

In contrast to other recycling processes (mechanical recycling, vacuum pyrolysis), tluidized-bed pyrolysis has a number of advantages. Different kinds of plastics can be degradated into monomers in higher yields than with other methods and without needing to mill wastes into small particle sizes. The most important advantages are that monomers produced can be purified before repolymerization which allows production of a more valuable product and that the process allows continuous operation. 

Plastics waste comes from two main sources processing plants (ca. 10%) and post-use scrap (90%). The former is nearly totally reprocessed (i.e., > 96%) by the processors using the plastics (or mechanical) recycling methods. Recycling of the later material very much depends on the... 

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