Recycling polyethylene packaging

Franz, R., Recycled Polyethylene terephthalate) for direct food contact application, FDA submission CTS 71903, Petitioner Buhler A. G, Representative Laboratory Fraunhofer Institute for Process Engineering and Packaging, Freising, Germany, Petition to the FDA, 2000. 

Applications of Recycled Polyethylene Terephthalate in Food Packaging... 

Nor is it tme that poly(ethylene terephthalate) (PET) and high density polyethylene (HDPE) packaging are hsted as 1 and 2 in the Society of the Plastics Industry (SPI) recycling coding system because they are the most recyclable. The numbers assigned to each plastic in the SPI coding system are purely arbitrary and do not redect the material s recyclabihty. 

The ethylene resides in the reactor about two minutes, and as it polymerizes, it remains dissolved in the cyclohexane. To keep the concentration of polyethylene in the cyclohexane at 35-40%, a solution of the feed, solvent, and product are continuously drawn off. Downstream, the ethylene flashes off to be recycled in a flash tower. A precipitator removes the polyethylene from the cyclohexane by centrifuge. The polyethylene is steam-stripped to remove any remaining cyclohexane, then dried, extruded, pelletized, and packaged. 

As a structural element to support paneling and wall mounts, there is growing interest in the use of plastic lumber produced using the recycled scrap or waste of polyethylene (HDPE), polypropylene, and PET materials from various packaging and other high turnover applications... 

The most difficult recyclates are the MSW, which usually consists of more or less dirty plastics of various types and sources. According to one report [15] the plastic portion of MSW contains typically 50% PE (mainly low density polyethylene, LDPE), 8-14% polypropylene (PP), 15% polystyrene (PS), 10% polyvinylchloride (PVC) and 5% polyethylene terephthalate (PET), and 5% other polymers, while the hard packaging fraction consists of approx. 60% of PP and HDPE [16]. 

Franz, R., Mauer, A., and Welle, F. (2004). European survey on post-consumer polyethylene terephthalate) (PET) materials to determine contamination levels and maximum consumer exposure from food packages made from recycled PET. Food Addit. Contam. 21, 265-286. 

R. FRANZ, F. BAYER, F. WELLE, Guidance and criteria for safe recycling of post consumer polyethylene terephthalate (PET) into new food packaging applications, EU Report 21155, ISBN 92-894-6776-2, Office for Official Publications of the European Communities, Luxembourg, 2004. 

R. FRANZ, Programme on the recyclability of food packaging materials with respect to food safety considerations - Polyethylene terephthalate (PET), paper board and plastics covered by functional barriers. Food Additives and Contaminants, 2002, 19(snpplement), 93-110. 

The relative amounts of various plastics produced for packaging in 1987 are shown here. 87 percent of the plastics sold for packaging are thermoplastic. Polyethylenes and PVC are the most recyclable forms of plastic because they are so easy to remelt and reprocess. 

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