Post-consumer recycled plastic

Gajanan Bhat (The University of Tennessee in Knoxville) who contributed the chapter on Processing of Post-Consumer Recycled Plastics, writes, Plastics continue to replace traditional materials in many applications and are being used in several new products. Many advantages of plastics in their performance as well as in the ease of their fabrication have contributed to their growth. Since... 

Innovation in the fabric softener business not only focused on compositions, but also on packaging. As an alternative to plastic bottles, heat-sealed flexible polyethylene pouches were introduced to the market in the early 1980s [7], followed by several other containers free-standing flexible pouches with a solid base, different bag in a box rigid units, and refill cartons coated with chemically resistant polymers. These novelties led to a 40% reduction in plastic bottle consumption, the use of more biodegradable, renewable, easily recycled material, and a decrease in the packaging and distribution cost. New bottles made of 100% post consumer recycled plastic sandwiched between two layers of virgin resin also became available [7],... 

In principle, it is reasonable to assume that recycled industrial scrap may be regarded as virgin polymer from the point of view of stabilization, and should therefore be re-stabilized in the same way as the original material, prior to re-processing. This holds good also for stabilization of post-consumer recycled plastics but, in this case, other factors should also be considered, such as degree of degradation, amount of residual stabilizers and extent of contamination. 

The FDA requires manufacturers using recycled plastic (called post-consumer recycled plastic) in food contact-applications demonstrate that the recycling process removes possible contaminants, and guidance on specific testing approaches to be used is provided by the FDA (FDA 2014b). While no specific limits were listed for cadmium in recycled food contact plastics, if the estimated dietary intake of a contaminant is less than 1.5 pg per person per day, the FDA considers this exposure to be of negligible risk (FDA 2006). 

Davos, 15th-19thMay 1995, paper 20. 8(13) FEEDSTOCK RECYCLING OE POST CONSUMER WASTE PLASTICS Niemann K... 

Plastic lumber can be manufactured from mixed-polymer post-consumer recycled materials. One example incorporates polyethylene and polypropylene into a final material. How do processors achieve this incorporation in light of the immiscibility of the two polymers ... 

Biodegradable materials are created specifically with recyclability or disposal in mind. Recycling techniques for post-consumer biodegradable plastic products have two important features, which distinguish them from conventional polymers their biodegradability or compostability and the use of renewable resources in their manufacture. 

Plastics waste arises at the levels of production, conversion, and consumption. In the first two categories source separation, identification, and recycling, is straightforward. Such simple source separation concepts no longer hold for post-consumer recycling, where entropy is immense plastic products both geographically and functionally are widely spread, more often than not compounded with unknown additives, or mixed, soiled, composite, and difficult to collect at a reasonable cost. 

Although direct liquefaction of waste plastic looked promising, problems associated with impurities (paper, aluminum, etc.) and chlorine derived from PVC caused operational difficulties. Consequently, it currently appears that the first step of any feedstock recycling process for waste plastics or tires should be pyrolysis, which allows much easier separation of solid impurities and chlorine. Research on pyrolysis of post-consumer plastic has been carried out by Kaminsky and co-workers [17, 18], Conrad Industries [19, 20], and Shah et al. [21]. Shah et al. [21] conducted pyrolysis experiments on relatively dirty post-consumer waste plastic obtained from the DSD. The pyrolysis oils were then subjected to hydroprocessing to convert them into high-quality transportation fuels (gasoline, kerosene, diesel). 

A widespread solution, in terms of application and market volume, could be the recycling of single materials or homogeneous fractions obtained from a separation process of the mixture. In fact, the samples obtained from single homogeneous fractions show a general performance far greater than that of samples produced from mixed plastics. Separation of post-consumer mixed plastics (municipal waste) into four fractions—polyolefins (PO), PS, PVC, and PET—is commonly adequate. 

ExxonMobils Exact Plastomers are polyolefins produced using a comonomer, butene, hexene, and octene, which significantly affects the properties of the plastic and can be used as a property enhancer in blends with LLDPE or post-consumer recycled Hdpe.[ioi4] See pjg 30.01. 

Waste management and recycling alternatives are presented and discussed in Chapter 3. The poor reputation of used plastics is gradually dissipating, as methods to recover and recycle post-consumer waste plastics improve and reliable high-quality supplies of reusable material can be guaranteed. 

Sitek, F., Restabdization Upgrades Post-consumer Recyclate, Modem Plastics, Oct. 1993, pp. 64-68. 

The information in Part I is from Post-Consumer Mixed Plastics Recycling-Characterization, Collection, Costs and Markets, prepared by Bruce A. Hegberg, William H. Hallenbeck, and Gary R. Brenniman of the University of Illinois Center for Solid Waste Management and Research for the Illinois Department of Energy and Natural Resources, Office of Solid Waste and Renewable Resources, January 1991. 

However, in order to expand the recovery and recycling of plastics and decrease the amount of waste disposed in landfills, it will be necessary to overcome these difficulties. Because of its heterogeneous nature and the amount of contaminants present, separation of post-consumer mixed plastic waste is the most difficult. Waste plastics from industrial operations are cleaner and more homogeneous in resin type and scrap form than postconsumer plastics. The term "mixed plastics" has been used to describe broad scale processing of post-consumer plastic waste, although no formal definition yet exists. In its broadest sense, mixed plastics means a collection of a mixture of plastic resins or a mixture... 

Petra, Post-consumer recycled PET resin, AlliedSignal Inc., AlliedSignal Plastics... 

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