An excellent article in Chemical and Engineering News (Sept. 2018, by Alexander Tullo, see link at very bottom) is titled “Should energy be recovered from plastics?”
Columbia University has been studying the subject of used plastics for nearly ten years. One can find several theses and other documents at our web page www.wtert.org. After many efforts by chemical industry and others to recycle used plastics, for technical and economic reasons, only 10% of the plastic waste is recycled to materials , anywhere in the world. In the U.S., another 10% mixed in urban waste, is combusted with production of electricity in 77 waste-to-energy WTE plants, such as the one described in the CEN article. The other 80% is landfilled or discarded on land and water.
Mixed plastic wastes have a calorific value 20% less than fuel oil and, as noted in this article, are a good feedstock for pyrolysis plants or WTE plants designed to be fueled by mixed plastics. The technology is available but the petrochemical industry must help to build and operate such plants.
Prof. Nickolas Themelis, Columbia University