High-value recycled plastics, production

This chapter has summarized research conducted on feedstock recycling of waste plastic into light oil products ( Cs-C2o) suitable for transportation fuels (gasoline, jet fuel, and diesel fuel) and a high value product, lubricating oil. The principal results are summarized below. 

It shall suffice in the context of the present review to point out that, while some products with high quality and value are being made from recycled plastics, most of the applications are low-cost manufactured parts. These include [B.83] the following. 

Most end-use markets for recycled plastic bottles require that they be separated by resin type and color. This ensures high end-use value for new products incorporating substantial amounts of the recycled resin. PVC bottles, like PET bottles, are very recyclable. Manual sorting of nonpigmented PVC and clear PET bottles is difficult because they look alike. When the two types are received commingled, the reprocessor can experience quality deficiencies due to rheological incompatibilities between these two resins. Therefore, all attempts to separate and remove these two resins must be made prior to recycling. 

Tires are one of the most durable technological products manufactured today. They are a resilient, durable composite of fabric, steel, carbon black, natural rubber, and synthetic polymers. The qualities that make tires or other engineered rubber products a high-value item create a special challenge of disposal. Tires and other rubber products, such as conveyor belts and hydrauUc hoses, are not biodegradable and cannot be recycled like glass, aluminum, or plastic. Four potential applications for such products entering the solid waste stream have been identified ... 

After plastics have been collected and sorted, the alternative to re-use as materials is to burn them in a proper station to generate energy. The costs added in the recycle for use as a material are eliminated and a product is obtained which has a simple market value. In Japan where land is scarce and thus the cost of landfill is high, incineration of plastics in municipal solid waste has been accepted by the general public, though still surrounded by some controversy about emissions. 

There are recycling opportunities for other plastics beyond the few recognized by SPI RICs. The automobile industry, for instance, utilizes a series of engineering thermoplastics that have a built-in market if they can be recovered and reprocessed. These high value plastics include polyamides (Nylon 6, Nylon 6,6, etc.), polycarbonates (PC), acrylics (PMMA), styrenics (ABS), and blends (TPO, PC/PBT, PC/ ABS, etc.). Their higher value and demand allow recyclers the opportunity to practice more exotic recovery procedures and still have an economically viable product. 

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