A Novel Solvent-Based Recycling Technology: From Theory to Pilot Plant

Session på engelska*

We will present a novel solvent-based technology for the extraction of single pure resins, of the highest quality from a variety of wastes, including multi-layer films, mixed plastic waste, post-consumer-recycled (PCR) and post-industrial-recycled (PIR) materials, and municipal solid waste (MSW). The technology is called Solvent Targeted Recovery and Precipitation (STRAP). Numerous lab-scale experiments have been conducted to prove the concept. The key to successfully implementing STRAP is the ability to pre-select solvents and temperatures to selectively dissolve a single polymer from all components in the mix. An extensive fundamental understanding of dissolution that enables a successful operation has been developed. Solvent selection applied a first-principles molecular modeling approach to predict temperature-dependent polymer solubilities in solvents rapidly. The technology has been scaled to a 0.5 ton/day continuous process, which is the basis for the next industrial scale. The technology requires relatively low temperatures (90-135oC) and equipment that is available in the chemical industry. Extensive techno-economic and lifecycle assessments showed (i) a STRAP system can be profitable as a stand-alone system at a 4,000 ton/y facility, with great advantage of size, and (ii) due to the low process energy, the greenhouse gas (GHG) emissions are reduced by up to 90% in comparison to fossil-based polymer production. Partnership with resin producers and resin converters enabled the testing of the extracted resins for reuse in their original applications. The single most important economic factor is the rate of solvent recovery (better than 99.9%) of the solvent used. Of particular importance is the ability to use STRAP with MSW, which separates biogenic material and resins. The former can be used instead of biomass at a significantly lower cost, whereas the former are important co-products with high added value.