Plastics are the fastest-growing component of municipal solid waste in the USA, and over the past decade there has been increasing public demand for plastics recycling. However, the necessity to separate the various plastic resins to make their recycling possible, combined with the low cost of virgin resins, make this technically difficult and expensive.
Most sorting of plastic waste is done manually, and this method has been constrained to the diversion of only one or two types of plastics, because human sorters are incapable of distinguishing different plastics. A number of technologies are being developed in order to address this problem. Use of these technologies requires considerable capital investment and this makes many of them economically unfeasible at present. The federal, state, and local governments in the USA have continued to explore demand-side policy measures in an effort to promote market formation and operation. Where they have been successful, in the establishment of markets for recycled polyethylene terepthalate (PET), and high-density polyethylene (HDPE) resins, demand has outpaced supply, highlighting the need to find more effective methods to sort and divert different plastic resins. Even with these supply shortages, and with prices for virgin PET and HDPE at historic highs, however, most plastics recycling remains only marginally profitable. This demonstrates the need for continued policy support for the still-developing plastics recycling industry and recycled-plastics market.
An analysis of the factors driving the recycling of PET, HDPE and polypropylene indicates that, as long as manual sorting is used, it would make sense for supply- and demand-side policies to focus on the recycling of particular plastic products that are easy to recognize, rather than resins that are not. Appropriate policies can help make specific products easily recognizable sources of specific resins. Such policies, implemented in conjunction with measures designed to facilitate capital investments and promote the establishment and operation of markets for all resins, are necessary to increase significantly the recycling of plastic waste above present levels.